Broadcast signal transmission/reception device and method

ABSTRACT

A broadcast signal transmission method is disclosed. The broadcast signal transmission method according to one embodiment of the present invention comprises the steps of: processing video data and audio data; encoding a broadcast service component, including the video data and audio data, and service layer signaling (SLS) information on the broadcast service component on the basis of a delivery protocol; subjecting the broadcast service component, the SLS information, and service list table (SLT) information to IP packetization; and subjecting the broadcast service component, the SLS information, and the SLT information to physical layer processing.

This application is a continuation of U.S. patent application Ser. No.15/765,761, filed Aug. 28, 2018, which is a National Stage Applicationof International Application No. PCT/KR2016/0011193, filed on Oct. 6,2016, which claims the benefit of U.S. Provisional Application No.62/238,684, filed on Oct. 7, 2015, U.S. Provisional Application No.62/253,090, filed on Nov. 9, 2015 and U.S. Provisional Application No.62/257,230, filed on Nov. 19, 2015, the contents of which are all herebyincorporated by reference herein in their entirety,

TECHNICAL FIELD

The present invention relates to a broadcast signal transmissionapparatus, a broadcast signal reception apparatus and a broadcast signalreception method.

BACKGROUND ART

As the transmission of an analog broadcast signal is terminated, varioustechniques for transmitting/receiving a digital broadcast signal arebeing developed. A digital broadcast signal may include a larger amountof video/audio data than an analog broadcast signal, and may furtherinclude various types of additional data in addition to video/audiodata.

DISCLOSURE Technical Problem

A digital broadcast system may provide high definition (HD) images,multi-channel (multiple channels) audio, and various additionalservices. However, for digital broadcasting, data transmissionefficiency for the transmission of a large amount of data, therobustness of a transmission/reception network, and network flexibilityin which a mobile reception apparatus is taken into consideration mustbe improved.

Technical Solution

In order to solve the aforementioned technological problems, the presentinvention proposes a broadcast signal transmission method and abroadcast signal transmission apparatus.

A broadcast signal transmission method according to an embodiment of thepresent invention includes the steps of processing video data and audiodata; encoding a broadcast service component including the video dataand the audio data and service layer signaling (SLS) information aboutthe broadcast service component based on a delivery protocol, whereinthe SLS information provides the discovery and acquisition of thebroadcast service component, and the delivery protocol includes at leastone of a real-time object delivery over unidirectional transport (ROUTE)protocol and an MPEG media transport (MMT) protocol; IP-packatizing thebroadcast service component, the SLS information, and service list table(SLT) information, wherein the SLT information includes bootstrapinformation for obtaining the SLS information; andphysical-layer-processing the broadcast service component, the SLSinformation, and the SLT information.

In the broadcast signal transmission method according to an embodimentof the present invention, the processing of the audio data may furtherinclude the step of embedding a watermark payload in the audio data, thewatermark payload may include domain type information, service fieldinformation including a server code, interval field informationincluding an interval code, and query flag information indicative of anavailability of a dynamic event, the server code may identify a serverfor the acquisition of supplementary content, and the interval code mayidentify the interval of content in which a watermark payload has beenembedded.

In the broadcast signal transmission method according to an embodimentof the present invention, the watermark payload may signal a displayoverride indicator instructing content to be presented without specificoverlaid graphics or another alternate content.

In the broadcast signal transmission method according to an embodimentof the present invention, the availability of the dynamic event data maybe indicated by a change of a value of the query flag informationbetween the successive watermark payloads within a watermark segment,and a URL constructed from the watermark payload may indicate theresource of a dynamic event server when the dynamic event data isavailable.

In the broadcast signal transmission method according to an embodimentof the present invention, the processing of the video data may includethe step of embedding a watermark payload in the video data, and thewatermark payload may include at least one watermark message.

In the broadcast signal transmission method according to an embodimentof the present invention, the watermark payload may include a displayoverride message, the display override message may instruct audio andvideo to be output without overlaid graphics or any obstruction, and thedisplay override message may include override duration informationindicative of duration for which a display override continues.

In the broadcast signal transmission method according to an embodimentof the present invention, the SLS information may include applicationsignaling information to control an app-based enhancement if a broadcastservice may include the app-based enhancement.

Furthermore, a broadcast signal transmission apparatus according to anembodiment of the present invention includes a video data processorprocessing video data, an audio data processor processing audio data, adelivery layer encoder encoding a broadcast service component includingthe video data and the audio data and service layer signaling (SLS)information about the broadcast service component based on a deliveryprotocol, wherein the SLS information provides the discovery andacquisition of the broadcast service component and the delivery protocolmay include at least one of a real-time object delivery overunidirectional transport (ROUTE) protocol and an MPEG media transport(MMT) protocol, an IP packetizer IP-packatize the broadcast servicecomponent, the SLS information, and service list table (SLT)information, wherein the SLT information may include bootstrapinformation for obtaining the SLS information, and a physical layerprocessor physical-layer-processing the broadcast service component, theSLS information, and the SLT information.

In the broadcast signal transmission apparatus according to anembodiment of the present invention, the audio data processor may embeda watermark payload in the audio data, the watermark payload may includedomain type information, service field information including a servercode, interval field information including an interval code, and queryflag information indicative of an availability of a dynamic event, theserver code may identify a server for the acquisition of supplementarycontent, and the interval code may identify the interval of content inwhich a watermark payload has been embedded.

In the broadcast signal transmission apparatus according to anembodiment of the present invention, the watermark payload may signal adisplay override indicator instructing content to be presented withoutspecific overlaid graphics or another alternate content.

In the broadcast signal transmission apparatus according to anembodiment of the present invention, the availability of the dynamicevent data may be indicated by a change of a value of the query flaginformation between the successive watermark payloads within a watermarksegment, and a URL constructed from the watermark payload may indicatethe resource of a dynamic event server when the dynamic event data isavailable.

In the broadcast signal transmission apparatus according to anembodiment of the present invention, the video data processor may embeda watermark payload in the video data, and the watermark payload mayinclude at least one watermark message.

In the broadcast signal transmission apparatus according to anembodiment of the present invention, the watermark payload may include adisplay override message, the display override message may instructaudio and video to be output without overlaid graphics or anyobstruction, and the display override message may include overrideduration information indicative of duration in which a display overridecontinues.

In the broadcast signal transmission apparatus according to anembodiment of the present invention, the SLS information may includeapplication signaling information to control an app-based enhancement ifa broadcast service may include the app-based enhancement.

Advantageous Effects

The present invention can provide various broadcast services byprocessing data based on a service characteristic and controllingquality of service (QoS) for each service or service component.

The present invention can achieve transmission flexibility bytransmitting various broadcast services through the same radio frequency(RF) signal bandwidth.

According to the present invention, although a mobile receptionapparatus is used or in the case of an indoor environment, there can beprovided broadcast signal transmission and reception methods andapparatuses capable of receiving a digital broadcast signal without anerror.

The present invention can effectively support a next-generationbroadcast service in an environment that supports next-generation hybridbroadcasting using a terrestrial broadcast network and the Internet.

Hereinafter, additional effects of the present invention may bedescribed along with the configuration of the invention.

DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram showing a protocol stack according to an embodimentof the present invention.

FIG. 2 is a diagram showing a service discovery process according to anembodiment of the present invention.

FIG. 3 is a diagram showing a low level signaling (LLS) table and aservice list table (SLT) according to an embodiment of the presentinvention.

FIG. 4 is a diagram showing an USBD and an S-TSID delivered to a ROUTEaccording to an embodiment of the present invention.

FIG. 5 is a diagram showing a USBD delivered to an MMT according to anembodiment of the present invention.

FIG. 6 is a diagram showing a link layer operation according to anembodiment of the present invention.

FIG. 7 is a diagram showing a link mapping table (LMT) according to anembodiment of the present invention.

FIG. 8 shows the structure of a broadcast signal transmission apparatusfor a next-generation broadcast service according to an embodiment ofthe present invention.

FIG. 9 shows a writing operation of a time interleaver according to anembodiment of the present invention.

FIGS. 10a, 10b, 10c are diagrams showing a block diagram of aninterleaving address generator including a main-PRBS generator and asub-PRBS generator according to each FFT mode included in a frequencyinterleaver according to an embodiment of the present invention.

FIGS. 11a , 11 b, and 11 c show an application signaling table accordingto an embodiment of the present invention.

FIG. 12 shows an application control code according to an embodiment ofthe present invention.

FIG. 13 is an embodiment of an app use type according to the presentinvention.

FIG. 14 shows an application lifetime table (ALT) according to anotherembodiment of the present invention.

FIGS. 15 and 16 show the life cycle state of an application and thetransition of states according to an embodiment of the presentinvention.

FIG. 17 shows a video watermark payload according to an embodiment ofthe present invention.

FIG. 18 shows a watermark message according to an embodiment of thepresent invention.

FIG. 19 shows the type of message according to the identifier of awatermark message according to an embodiment of the present invention.

FIG. 20 shows a dynamic event message according to an embodiment of thepresent invention.

FIG. 21 shows a display override message according to an embodiment ofthe present invention.

FIG. 22 shows an audio watermark payload according to an embodiment ofthe present invention.

FIG. 23 shows (a) small domain information and (b) large domaininformation included in the audio watermark payload.

FIG. 24 shows a recovery file format according to an embodiment of thepresent invention.

FIG. 25 shows component description information according to anembodiment of the present invention.

FIG. 26 shows a broadcast signal transmitter and a broadcast signalreceiver according to an embodiment of the present invention.

FIG. 27 shows a broadcast signal transmission method according to anembodiment of the present invention.

BEST MODE

Preferred embodiments of the present invention are describedspecifically, and examples thereof are shown in the accompanyingdrawings. The following detailed description for which reference is madeto the accompanying drawings is intended to describe preferredembodiments of the present invention rather than to describe onlyembodiments that may be implemented based on embodiments of the presentinvention. The following detailed description includes details in orderto provide thorough understanding of the present invention. However, itis evident to those skilled in the art that the present invention may beexecuted without such details.

Most of terms used in the present invention have been selected fromcommon terms widely used in a corresponding field, but some terms havebeen randomly selected by the applicant and meanings thereof aredescribed in detail in the following description, if necessary.Accordingly, the present invention should be understood based on anintended meaning of a term not the name or meaning of the term.

The present invention provides an apparatus and method for transmittingand receiving broadcast signals for future broadcast services. Futurebroadcast services according to an embodiment of the present inventioninclude a terrestrial broadcast service, a mobile broadcast service, aUHDTV service, etc. The present invention may process broadcast signalsfor the future broadcast services through non-MIMO or MIMO according toone embodiment. A non-MIMO scheme according to an embodiment of thepresent invention may include a multiple input single output (MISO)scheme, a single input single output (SISO) scheme, etc. The presentinvention proposes a physical profile (or system) optimized to minimizereceiver complexity while attaining the performance required for aparticular use case.

FIG. 1 is a diagram showing a protocol stack according to an embodimentof the present invention.

A service may be delivered to a receiver through a plurality of layers.First, a transmission side may generate service data. The service datamay be processed for transmission at a delivery layer of thetransmission side and the service data may be encoded into a broadcastsignal and transmitted over a broadcast or broadband network at aphysical layer.

In this case, the service data may be generated in an ISO base mediafile format (BMFF). ISO BMFF media files may be used forbroadcast/broadband network delivery, media encapsulation and/orsynchronization format. In this case, the service data is all datarelated to the service and may include service components configuring alinear service, signaling information thereof, non real time (NRT) dataand other files.

The delivery layer will be described. The delivery layer may provide afunction for transmitting service data. The service data may bedelivered over a broadcast and/or broadband network.

Broadcast service delivery may include two methods.

As a first method, service data may be processed in media processingunits (MPUs) based on MPEG media transport (MMT) and transmitted usingan MMT protocol (MMTP). In this case, the service data delivered usingthe MMTP may include service components for a linear service and/orservice signaling information thereof.

As a second method, service data may be processed into DASH segments andtransmitted using real time object delivery over unidirectionaltransport (ROUTE), based on MPEG DASH. In this case, the service datadelivered through the ROUTE protocol may include service components fora linear service, service signaling information thereof and/or NRT data.That is, the NRT data and non-timed data such as files may be deliveredthrough ROUTE.

Data processed according to MMTP or ROUTE protocol may be processed intoIP packets through a UDP/IP layer. In service data delivery over thebroadcast network, a service list table (SLT) may also be delivered overthe broadcast network through a UDP/IP layer. The SLT may be deliveredin a low level signaling (LLS) table. The SLT and LLS table will bedescribed later.

IP packets may be processed into link layer packets in a link layer. Thelink layer may encapsulate various formats of data delivered from ahigher layer into link layer packets and then deliver the packets to aphysical layer. The link layer will be described later.

In hybrid service delivery, at least one service element may bedelivered through a broadband path. In hybrid service delivery, datadelivered over broadband may include service components of a DASHformat, service signaling information thereof and/or NRT data. This datamay be processed through HTTP/TCP/IP and delivered to a physical layerfor broadband transmission through a link layer for broadbandtransmission.

The physical layer may process the data received from the delivery layer(higher layer and/or link layer) and transmit the data over thebroadcast or broadband network. A detailed description of the physicallayer will be given later.

The service will be described. The service may be a collection ofservice components displayed to a user, the components may be of variousmedia types, the service may be continuous or intermittent, the servicemay be real time or non real time, and a real-time service may include asequence of TV programs.

The service may have various types. First, the service may be a linearaudio/video or audio service having app based enhancement. Second, theservice may be an app based service, reproduction/configuration of whichis controlled by a downloaded application. Third, the service may be anESG service for providing an electronic service guide (ESG). Fourth, theservice may be an emergency alert (EA) service for providing emergencyalert information.

When a linear service without app based enhancement is delivered overthe broadcast network, the service component may be delivered by (1) oneor more ROUTE sessions or (2) one or more MMTP sessions.

When a linear service having app based enhancement is delivered over thebroadcast network, the service component may be delivered by (1) one ormore ROUTE sessions or (2) zero or more MMTP sessions. In this case,data used for app based enhancement may be delivered through a ROUTEsession in the form of NRT data or other files. In one embodiment of thepresent invention, simultaneous delivery of linear service components(streaming media components) of one service using two protocols may notbe allowed.

When an app based service is delivered over the broadcast network, theservice component may be delivered by one or more ROUTE sessions. Inthis case, the service data used for the app based service may bedelivered through the ROUTE session in the form of NRT data or otherfiles.

Some service components of such a service, some NRT data, files, etc,may be delivered through broadband (hybrid service delivery).

That is, in one embodiment of the present invention, linear servicecomponents of one service may be delivered through the MMT protocol. Inanother embodiment of the present invention, the linear servicecomponents of one service may be delivered through the ROUTE protocol.In another embodiment of the present invention, the linear servicecomponents of one service and NRT data (NRT service components) may bedelivered through the ROUTE protocol. In another embodiment of thepresent invention, the linear service components of one service may bedelivered through the MMT protocol and the NRT data (NRT servicecomponents) may be delivered through the ROUTE protocol. In theabove-described embodiments, some service components of the service orsome NRT data may be delivered through broadband. In this case, the appbased service and data regarding app based enhancement may be deliveredover the broadcast network according to ROUTE or through broadband inthe form of NRT data. NRT data may be referred to as locally cacheddata.

Each ROUTE session includes one or more LCT sessions for wholly orpartially delivering content components configuring the service. Instreaming service delivery, the LCT session may deliver individualcomponents of a user service, such as audio, video or closed captionstream. The streaming media is formatted into a DASH segment.

Each MMTP session includes one or more MMTP packet flows for deliveringall or some of content components or an MMT signaling message. The MMTPpacket flow may deliver a component formatted into MPU or an MMTsignaling message.

For delivery of an NRT user service or system metadata, the LCT sessiondelivers a file based content item. Such content files may includeconsecutive (timed) or discrete (non-timed) media components of the NRTservice or metadata such as service signaling or ESG fragments. Systemmetadata such as service signaling or ESG fragments may be deliveredthrough the signaling message mode of the MMTP.

A receiver may detect a broadcast signal while a tuner tunes tofrequencies. The receiver may extract and send an SLT to a processingmodule. The SLT parser may parse the SLT and acquire and store data in achannel map. The receiver may acquire and deliver bootstrap informationof the SLT to a ROUTE or MMT client. The receiver may acquire and storean SLS. USBD may be acquired and parsed by a signaling parser.

FIG. 2 is a diagram showing a service discovery procedure according toone embodiment of the present invention.

A broadcast stream delivered by a broadcast signal frame of a physicallayer may carry low level signaling (LLS). LLS data may be carriedthrough payload of IP packets delivered to a well-known IP address/port.The LLS may include an SLT according to type thereof. The LLS data maybe formatted in the form of an LLS table. A first byte of every UDP/IPpacket carrying the LLS data may be the start of the LLS table. Unlikethe shown embodiment, an IP stream for delivering the LLS data may bedelivered to a PLP along with other service data.

The SLT may enable the receiver to generate a service list through fastchannel scan and provides access information for locating the SLS. TheSLT includes bootstrap information. This bootstrap information mayenable the receiver to acquire service layer signaling (SLS) of eachservice. When the SLS, that is, service signaling information, isdelivered through ROUTE, the bootstrap information may include an LCTchannel carrying the SLS, a destination IP address of a ROUTE sessionincluding the LCT channel and destination port information. When the SLSis delivered through the MMT, the bootstrap information may include adestination IP address of an MMTP session carrying the SLS anddestination port information.

In the shown embodiment, the SLS of service #1 described in the SLT isdelivered through ROUTE and the SLT may include bootstrap informationsIP1, dIP1 and dPort1 of the ROUTE session including the LCT channeldelivered by the SLS. The SLS of service #2 described in the SLT isdelivered through MMT and the SLT may include bootstrap informationsIP2, dIP2 and dPort2 of the MMTP session including the MMTP packet flowdelivered by the SLS.

The SLS is signaling information describing the properties of theservice and may include receiver capability information forsignificantly reproducing the service or providing information foracquiring the service and the service component of the service. Wheneach service has separate service signaling, the receiver acquiresappropriate SLS for a desired service without parsing all SLSs deliveredwithin a broadcast stream.

When the SLS is delivered through the ROUTE protocol, the SLS may bedelivered through a dedicated LCT channel of a ROUTE session indicatedby the SLT In some embodiments, this LCT channel may be an LCT channelidentified by tsi=0. In this case, the SLS may include a user servicebundle description (USBD)/user service description (USD), service-basedtransport session instance description (S-TSID) and/or mediapresentation description (MPD).

In this case, USBD/USD is one of SLS fragments and may serve as asignaling hub describing detailed description information of a service.The USBD may include service identification information, devicecapability information, etc. The USBD may include reference information(URI reference) of other SLS fragments (S-TSID, MPD, etc.). That is, theUSBD/USD may reference the S-TSID and the MPD. In addition, the USBD mayfurther include metadata information for enabling the receiver to decidea transmission mode (broadcast/broadband network). A detaileddescription of the USBD/USD will be given below.

The S-TSID is one of SLS fragments and may provide overall sessiondescription information of a transport session carrying the servicecomponent of the service. The S-TSID may provide the ROUTE sessionthrough which the service component of the service is delivered and/ortransport session description information for the LCT channel of theROUTE session. The S-TSID may provide component acquisition informationof service components associated with one service. The S-TSID mayprovide mapping between DASH representation of the MPD and the tsi ofthe service component. The component acquisition information of theS-TSID may be provided in the form of the identifier of the associatedDASH representation and tsi and may or may not include a PLP ID in someembodiments. Through the component acquisition information, the receivermay collect audio/video components of one service and perform bufferingand decoding of DASH media segments. The S-TSID may be referenced by theUSBD as described above. A detailed description of the S-TSID will begiven below.

The MPD is one of SLS fragments and may provide a description of DASHmedia presentation of the service. The MPD may provide a resourceidentifier of media segments and provide context information within themedia presentation of the identified resources. The MPD may describeDASH representation (service component) delivered over the broadcastnetwork and describe additional DASH presentation delivered overbroadband (hybrid delivery). The MPD may be referenced by the USBD asdescribed above.

When the SLS is delivered through the MMT protocol, the SLS may bedelivered through a dedicated MMTP packet flow of the MMTP sessionindicated by the SLT. In some embodiments, the packet_id of the MMTPpackets delivering the SLS may have a value of 00. In this case, the SLSmay include a USBD/USD and/or MMT packet (MP) table.

In this case, the USBD is one of SLS fragments and may describe detaileddescription information of a service as in ROUTE. This USBD may includereference information (URI information) of other SLS fragments. The USBDof the MMT may reference an MP table of MMT signaling. In someembodiments, the USBD of the MMT may include reference information ofthe S-TSID and/or the MPD. In this case, the S-TSID is for NRT datadelivered through the ROUTE protocol. Even when a linear servicecomponent is delivered through the MMT protocol, NRT data may bedelivered via the ROUTE protocol. The MPD is for a service componentdelivered over broadband in hybrid service delivery. The detaileddescription of the USBD of the MMT will be given below.

The MP table is a signaling message of the MMT for MPU components andmay provide overall session description information of an MMTP sessioncarrying the service component of the service. In addition, the MP tablemay include a description of an asset delivered through the MMTPsession. The MP table is streaming signaling information for MPUcomponents and may provide a list of assets corresponding to one serviceand location information (component acquisition information) of thesecomponents. The detailed description of the MP table may be defined inthe MMT or modified. In this case, the asset is a multimedia dataentity, is combined by one unique ID, and may mean a data entity used toone multimedia presentation. The asset may correspond to servicecomponents configuring one service. A streaming service component (MPU)corresponding to a desired service may be accessed using the MP table.The MP table may be referenced by the USBD as described above.

The other MMT signaling messages may be defined. Additional informationassociated with the service and the MMTP session may be described bysuch MMT signaling messages.

The ROUTE session is identified by a source IP address, a destination IPaddress and a destination port number. The LCT session is identified bya unique transport session identifier (TSI) within the range of a parentROUTE session. The MMTP session is identified by a destination IPaddress and a destination port number. The MMTP packet flow isidentified by a unique packet id within the range of a parent MMTPsession.

In case of ROUTE, the S-TSID, the USBD/USD, the MPD or the LCT sessiondelivering the same may be referred to as a service signaling channel.In case of MMTP, the USBD/UD, the MMT signaling message or the packetflow delivering the same may be referred to as a service signalingchannel.

Unlike the shown embodiment, one ROUTE or MMTP session may be deliveredover a plurality of PLPs. That is, one service may be delivered throughone or more PLPs. Unlike the shown embodiment, in some embodiments,components configuring one service may be delivered through differentROUTE sessions. In addition, in some embodiments, components configuringone service may be delivered through different MMTP sessions. In someembodiments, components configuring one service may be divided anddelivered in a ROUTE session and an MMTP session. Although not shown,components configuring one service may be delivered through broadband(hybrid delivery).

FIG. 3 is a diagram showing a low level signaling (LLS) table and aservice list table (SLT) according to one embodiment of the presentinvention.

One embodiment t3010 of the LLS table may include information accordingto an LLS_table_id field, a provider_id field, an LLS_table_versionfield and/or an LLS_table_id field.

The LLS_table_id field may identify the type of the LLS table, and theprovider_id field may identify a service provider associated withservices signaled by the LLS table. In this case, the service provideris a broadcaster using all or some of the broadcast streams and theprovider_id field may identify one of a plurality of broadcasters whichis using the broadcast streams. The LLS_table_version field may providethe version information of the LLS table.

According to the value of the LLS_table_id field, the LLS table mayinclude one of the above-described SLT, a rating region table (RRT)including information on a content advisory rating, SystemTimeinformation for providing information associated with a system time, acommon alert protocol (CAP) message for providing information associatedwith emergency alert. In some embodiments, the other information may beincluded in the LLS table.

One embodiment t3020 of the shown SLT may include an @bsid attribute, an@sltCapabilities attribute, an sltInetUrl element and/or a Serviceelement. Each field may be omitted according to the value of the shownUse column or a plurality of fields may be present.

The @bsid attribute may be the identifier of a broadcast stream. The@sltCapabilities attribute may provide capability information requiredto decode and significantly reproduce all services described in the SLT.The sltInetUrl element may provide base URL information used to obtainservice signaling information and ESG for the services of the SLT overbroadband. The sltInetUrl element may further include an @urITypeattribute, which may indicate the type of data capable of being obtainedthrough the URL.

The Service element may include information on services described in theSLT, and the Service element of each service may be present. The Serviceelement may include an @serviceId attribute, an @sltSvcSeqNum attribute,an @protected attribute, an @majorChannelNo attribute, an@minorChannelNo attribute, an @serviceCategory attribute, an@shortServiceName attribute, an @hidden attribute, an@broadbandAccessRequired attribute, an @svcCapabilities attribute, aBroadcastSvcSignaling element and/or an svcInetUrl element.

The @serviceId attribute is the identifier of the service and the@sltSvcSeqNum attribute may indicate the sequence number of the SLTinformation of the service. The @protected attribute may indicatewhether at least one service component necessary for significantreproduction of the service is protected. The @majorChannelNo attributeand the @minorChannelNo attribute may indicate the major channel numberand minor channel number of the service, respectively.

The @serviceCategory attribute may indicate the category of the service.The category of the service may include a linear A/V service, a linearaudio service, an app based service, an ESG service, an EAS service,etc. The @shortServiceName attribute may provide the short name of theservice. The @hidden attribute may indicate whether the service is fortesting or proprietary use. The @broadbandAccessRequired attribute mayindicate whether broadband access is necessary for significantreproduction of the service. The @svcCapabilities attribute may providecapability information necessary for decoding and significantreproduction of the service.

The BroadcastSvcSignaling element may provide information associatedwith broadcast signaling of the service. This element may provideinformation such as location, protocol and address with respect tosignaling over the broadcast network of the service. Details thereofwill be described below.

The svcInetUrl element may provide URL information for accessing thesignaling information of the service over broadband. The sltInetUrlelement may further include an @urlType attribute, which may indicatethe type of data capable of being obtained through the URL.

The above-described BroadcastSvcSignaling element may include an@slsProtocol attribute, an @slsMajorProtocolVersion attribute, an@slsMinorProtocolVersion attribute, an @slsPlpId attribute, an@slsDestinationIpAddress attribute, an @slsDestinationUdpPort attributeand/or an @slsSourceIpAddress attribute.

The @slsProtocol attribute may indicate the protocol used to deliver theSLS of the service (ROUTE, MMT, etc.). The @slsMajorProtocolVersionattribute and the @slsMinorProtocolVersion attribute may indicate themajor version number and minor version number of the protocol used todeliver the SLS of the service, respectively.

The @slsPlpId attribute may provide a PLP identifier for identifying thePLP delivering the SLS of the service. In some embodiments, this fieldmay be omitted and the PLP information delivered by the SLS may bechecked using a combination of the information of the below-describedLMT and the bootstrap information of the SLT.

The @slsDestinationIpAddress attribute, the @slsDestinationUdpPortattribute and the @slsSourceIpAddress attribute may indicate thedestination IP address, destination UDP port and source IP address ofthe transport packets delivering the SLS of the service, respectively.These may identify the transport session (ROUTE session or MMTP session)delivered by the SLS. These may be included in the bootstrapinformation.

FIG. 4 is a diagram showing a USBD and an S-TSID delivered through ROUTEaccording to one embodiment of the present invention.

One embodiment t4010 of the shown USBD may have a bundleDescription rootelement. The bundleDescription root element may have auserServiceDescription element. The userServiceDescription element maybe an instance of one service.

The userServiceDescription element may include an @globalServiceIDattribute, an @serviceId attribute, an @serviceStatus attribute, an@fulIMPDUri attribute, an @sTSIDUri attribute, a name element, aserviceLanguage element, a capabilityCode element and/or adeliveryMethod element. Each field may be omitted according to the valueof the shown Use column or a plurality of fields may be present.

The @globalServiceID attribute is the globally unique identifier of theservice and may be used for link with ESG data(Service@globalServiceID). The @serviceId attribute is a referencecorresponding to the service entry of the SLT and may be equal to theservice ID information of the SLT. The @serviceStatus attribute mayindicate the status of the service. This field may indicate whether theservice is active or inactive.

The @fulIMPDUri attribute may reference the MPD fragment of the service.The MPD may provide a reproduction description of a service componentdelivered over the broadcast or broadband network as described above.The @sTSIDUri attribute may reference the S-TSID fragment of theservice. The S-TSID may provide parameters associated with access to thetransport session carrying the service as described above.

The name element may provide the name of the service. This element mayfurther include an @lang attribute and this field may indicate thelanguage of the name provided by the name element. The serviceLanguageelement may indicate available languages of the service. That is, thiselement may arrange the languages capable of being provided by theservice.

The capabilityCode element may indicate capability or capability groupinformation of a receiver necessary to significantly reproduce theservice. This information is compatible with capability informationformat provided in service announcement.

The deliveryMethod element may provide transmission related informationwith respect to content accessed over the broadcast or broadband networkof the service. The deliveryMethod element may include abroadcastAppService element and/or a unicastAppService element. Each ofthese elements may have a basePattern element as a sub element.

The broadcastAppService element may include transmission associatedinformation of the DASH representation delivered over the broadcastnetwork. The DASH representation may include media components over allperiods of the service presentation.

The basePattern element of this element may indicate a character patternused for the receiver to perform matching with the segment URL. This maybe used for a DASH client to request the segments of the representation.Matching may imply delivery of the media segment over the broadcastnetwork.

The unicastAppService element may include transmission relatedinformation of the DASH representation delivered over broadband. TheDASH representation may include media components over all periods of theservice media presentation.

The basePattern element of this element may indicate a character patternused for the receiver to perform matching with the segment URL. This maybe used for a DASH client to request the segments of the representation.Matching may imply delivery of the media segment over broadband.

One embodiment t4020 of the shown S-TSID may have an S-TSID rootelement. The S-TSID root element may include an @serviceId attributeand/or an RS element, Each field may be omitted according to the valueof the shown Use column or a plurality of fields may be present.

The @serviceId attribute is the identifier of the service and mayreference the service of the USBD/USD. The RS element may describeinformation on ROUTE sessions through which the service components ofthe service are delivered.

According to the number of ROUTE sessions, a plurality of elements maybe present. The RS element may further include an @bsid attribute, an@sIpAddr attribute, an @dIpAddr attribute, an @dport attribute, an@PLPID attribute and/or an LS element.

The @bsid attribute may be the identifier of a broadcast stream in whichthe service components of the service are delivered. If this field isomitted, a default broadcast stream may be a broadcast stream includingthe PLP delivering the SLS of the service. The value of this field maybe equal to that of the @bsid attribute.

The @sIpAddr attribute, the @dIpAddr attribute and the @dport attributemay indicate the source IP address, destination IP address anddestination UDP port of the ROUTE session, respectively. When thesefields are omitted, the default values may be the source address,destination IP address and destination UDP port values of the currentROUTE session delivering the SLS, that is, the S-TSID. This field maynot be omitted in another ROUTE session delivering the servicecomponents of the service, not in the current ROUTE session.

The @PLPID attribute may indicate the PLP ID information of the ROUTEsession. If this field is omitted, the default value may be the PLP IDvalue of the current PLP delivered by the S-TSID. In some embodiments,this field is omitted and the PLP ID information of the ROUTE sessionmay be checked using a combination of the information of thebelow-described LMT and the IP address/UDP port information of the RSelement.

The LS element may describe information on LCT channels through whichthe service components of the service are transmitted. According to thenumber of LCT channel, a plurality of elements may be present. The LSelement may include an @tsi attribute, an @PLPID attribute, an @bwattribute, an @startTime attribute, an @endTime attribute, a SrcFlowelement and/or a RepairFlow element.

The @tsi attribute may indicate the tsi information of the LCT channel.Using this, the LCT channels through which the service components of theservice are delivered may be identified. The @PLPID attribute mayindicate the PLP ID information of the LCT channel. In some embodiments,this field may be omitted. The @bw attribute may indicate the maximumbandwidth of the LCT channel. The @startTime attribute may indicate thestart time of the LCT session and the @endTime attribute may indicatethe end time of the LCT channel.

The SrcFlow element may describe the source flow of ROUTE. The sourceprotocol of ROUTE is used to transmit a delivery object and at least onesource flow may be established within one ROUTE session. The source flowmay deliver associated objects as an object flow.

The RepairFlow element may describe the repair flow of ROUTE. Deliveryobjects delivered according to the source protocol may be protectedaccording to forward error correction (FEC) and the repair protocol maydefine an FEC framework enabling FEC protection.

FIG. 5 is a diagram showing a USBD delivered through MMT according toone embodiment of the present invention.

One embodiment of the shown USBD may have a bundleDescription rootelement. The bundleDescription root element may have auserServiceDescription element. The userServiceDescription element maybe an instance of one service.

The userServiceDescription element may include an @globalServiceIDattribute, an @serviceId attribute, a Name element, a serviceLanguageelement, a contentAdvisoryRating element, a Channel element, ampuComponent element, a routeComponent element, a broadbandComponentelement and/or a ComponentInfo element. Each field may be omittedaccording to the value of the shown Use column or a plurality of fieldsmay be present.

The @globalServiceID attribute, the @serviceId attribute, the Nameelement and/or the serviceLanguage element may be equal to the fields ofthe USBD delivered through ROUTE. The contentAdvisoryRating element mayindicate the content advisory rating of the service. This information iscompatible with content advisory rating information format provided inservice announcement. The Channel element may include informationassociated with the service. A detailed description of this element willbe given below.

The mpuComponent element may provide a description of service componentsdelivered as the MPU of the service. This element may further include an@mmtPackageId attribute and/or an @nextMmtPackageId attribute. The@mmtPackageId attribute may reference the MMT package of the servicecomponents delivered as the MPU of the service. The @nextMmtPackageIdattribute may reference an MMT package to be used after the MMT packagereferenced by the @mmtPackageId attribute in terms of time. Through theinformation of this element, the MP table may be referenced.

The routeComponent element may include a description of the servicecomponents of the service. Even when linear service components aredelivered through the MMT protocol, NRT data may be delivered accordingto the ROUTE protocol as described above. This element may describeinformation on such NRT data. A detailed description of this elementwill be given below.

The broadbandComponent element may include the description of theservice components of the service delivered over broadband. In hybridservice delivery, some service components of one service or other filesmay be delivered over broadband. This element may describe informationon such data. This element may further an @fullMPDUri attribute. Thisattribute may reference the MPD describing the service componentdelivered over broadband. In addition to hybrid service delivery, thebroadcast signal may be weakened due to traveling in a tunnel and thusthis element may be necessary to support handoff between broadband andbroadband. When the broadcast signal is weak, the service component isacquired over broadband and, when the broadcast signal becomes strong,the service component is acquired over the broadcast network to secureservice continuity.

The ComponentInfo element may include information on the servicecomponents of the service. According to the number of service componentsof the service, a plurality of elements may be present. This element maydescribe the type, role, name, identifier or protection of each servicecomponent. Detailed information of this element will be described below.

The above-described Channel element may further include an @serviceGenreattribute, an @serviceIcon attribute and/or a ServiceDescriptionelement. The @serviceGenre attribute may indicate the genre of theservice and the @serviceIcon attribute may include the URL informationof the representative icon of the service. The ServiceDescriptionelement may provide the service description of the service and thiselement may further include an @serviceDescrText attribute and/or an@serviceDescrLang attribute. These attributes may indicate the text ofthe service description and the language used in the text.

The above-described routeComponent element may further include an@sTSIDUri attribute, an @sTSIDDestinationIpAddress attribute, an@sTSIDDestinationUdpPort attribute, an @sTSIDSourceIpAddress attribute,an @sTSIDMajorProtocolVersion attribute and/or an@sTSIDMinorProtocolVersion attribute.

The @sTSIDUri attribute may reference an S-TSID fragment. This field maybe equal to the field of the USBD delivered through ROUTE. This S-TSIDmay provide access related information of the service componentsdelivered through ROUTE. This S-TSID may be present for NRT datadelivered according to the ROUTE protocol in a state of deliveringlinear service component according to the MMT protocol.

The @sTSIDDestinationIpAddress attribute, the @sTSIDDestinationUdpPortattribute and the @sTSIDSourceIpAddress attribute may indicate thedestination IP address, destination UDP port and source IP address ofthe transport packets carrying the above-described S-TSID. That is,these fields may identify the transport session (MMTP session or theROUTE session) carrying the above-described S-TSID.

The @sTSIDMajorProtocolVersion attribute and the@sTSIDMinorProtocolVersion attribute may indicate the major versionnumber and minor version number of the transport protocol used todeliver the above-described S-TSID, respectively.

The above-described ComponentInfo element may further include an@componentType attribute, an @componentRole attribute, an@componentProtectedFlag attribute, an @componentId attribute and/or an@componentName attribute.

The @componentType attribute may indicate the type of the component. Forexample, this attribute may indicate whether the component is an audio,video or closed caption component. The @componentRole attribute mayindicate the role of the component. For example, this attribute mayindicate main audio, music, commentary, etc. if the component is anaudio component. This attribute may indicate primary video if thecomponent is a video component. This attribute may indicate a normalcaption or an easy reader type if the component is a closed captioncomponent.

The @componentProtectedFlag attribute may indicate whether the servicecomponent is protected, for example, encrypted. The @componentIdattribute may indicate the identifier of the service component. Thevalue of this attribute may be the asset_id (asset ID) of the MP tablecorresponding to this service component. The @componentName attributemay indicate the name of the service component.

FIG. 6 is a diagram showing link layer operation according to oneembodiment of the present invention.

The link layer may be a layer between a physical layer and a networklayer. A transmission side may transmit data from the network layer tothe physical layer and a reception side may transmit data from thephysical layer to the network layer (t6010). The purpose of the linklayer is to compress (abstract) all input packet types into one formatfor processing by the physical layer and to secure flexibility andexpandability of an input packet type which is not defined yet. Inaddition, the link layer may provide option for compressing(abstracting) unnecessary information of the header of input packets toefficiently transmit input data. Operation such as overhead reduction,encapsulation, etc. of the link layer is referred to as a link layerprotocol and packets generated using this protocol may be referred to aslink layer packets. The link layer may perform functions such as packetencapsulation, overhead reduction and/or signaling transmission.

At the transmission side, the link layer (ALP) may perform an overheadreduction procedure with respect to input packets and then encapsulatethe input packets into link layer packets. In addition, in someembodiments, the link layer may perform encapsulation into the linklayer packets without performing the overhead reduction procedure. Dueto use of the link layer protocol, data transmission overhead on thephysical layer may be significantly reduced and the link layer protocolaccording to the present invention may provide IP overhead reductionand/or MPEG-2 TS overhead reduction.

When the shown IP packets are input as input packets (t6010), the linklayer may sequentially perform IP header compression, adaptation and/orencapsulation. In some embodiments, some processes may be omitted. Forexample, the RoHC module may perform IP packet header compression toreduce unnecessary overhead. Context information may be extractedthrough the adaptation procedure and transmitted out of band. The IPheader compression and adaption procedure may be collectively referredto as IP header compression. Thereafter, the IP packets may beencapsulated into link layer packets through the encapsulationprocedure.

When MPEG 2 TS packets are input as input packets, the link layer maysequentially perform overhead reduction and/or an encapsulationprocedure with respect to the TS packets. In some embodiments, someprocedures may be omitted. In overhead reduction, the link layer mayprovide sync byte removal, null packet deletion and/or common headerremoval (compression). Through sync byte removal, overhead reduction of1 byte may be provided per TS packet. Null packet deletion may beperformed in a manner in which reinsertion is possible at the receptionside. In addition, deletion (compression) may be performed in a mannerin which common information between consecutive headers may be restoredat the reception side. Some of the overhead reduction procedures may beomitted. Thereafter, through the encapsulation procedure, the TS packetsmay be encapsulated into link layer packets. The link layer packetstructure for encapsulation of the TS packets may be different from thatof the other types of packets.

First, IP header compression will be described.

The IP packets may have a fixed header format but some informationnecessary for a communication environment may be unnecessary for abroadcast environment. The link layer protocol may compress the headerof the IP packet to provide a mechanism for reducing broadcast overhead.

IP header compression may employ a header compressor/decompressor and/oran adaptation module. The IP header compressor (RoHC compressor) mayreduce the size of each IP packet header based on the RoHC scheme.Thereafter, the adaptation module may extract context information andgenerate signaling information from each packet stream. A receiver mayparse signaling information associated with the packet stream and attachcontext information to the packet stream. The RoHC decompressor mayrestore the packet header to reconfigure an original IP packet.Hereinafter, IP header compression may mean only IP header compressionby a header compression or a combination of IP header compression and anadaptation process by an adaptation module. The same is true indecompressing.

Hereinafter, adaptation will be described.

In transmission of a single-direction link, when the receiver does nothave context information, the decompressor cannot restore the receivedpacket header until complete context is received. This may lead tochannel change delay and turn-on delay. Accordingly, through theadaptation function, configuration parameters and context informationbetween the compressor and the decompressor may be transmitted out ofband. The adaptation function may provide construction of link layersignaling using context information and/or configuration parameters. Theadaptation function may use previous configuration parameters and/orcontext information to periodically transmit link layer signalingthrough each physical frame.

Context information is extracted from the compressed IP packets andvarious methods may be used according to adaptation mode.

Mode #1 refers to a mode in which no operation is performed with respectto the compressed packet stream and an adaptation module operates as abuffer.

Mode #2 refers to a mode in which an IR packet is detected from acompressed packet stream to extract context information (static chain).After extraction, the IR packet is converted into an IR-DYN packet andthe IR-DYN packet may be transmitted in the same order within the packetstream in place of an original IR packet.

Mode #3 (t6020) refers to a mode in which IR and IR-DYN packets aredetected from a compressed packet stream to extract context information.A static chain and a dynamic chain may be extracted from the IR packetand a dynamic chain may be extracted from the IR-DYN packet. Afterextraction, the IR and IR-DYN packets are converted into normalcompression packets. The converted packets may be transmitted in thesame order within the packet stream in place of original IR and IR-DYNpackets.

In each mode, the context information is extracted and the remainingpackets may be encapsulated and transmitted according to the link layerpacket structure for the compressed IP packets. The context informationmay be encapsulated and transmitted according to the link layer packetstructure for signaling information, as link layer signaling.

The extracted context information may be included in a RoHC-Udescription table (RDT) and may be transmitted separately from the RoHCpacket flow. Context information may be transmitted through a specificphysical data path along with other signaling information. The specificphysical data path may mean one of normal PLPs, a PLP in which low levelsignaling (LLS) is delivered, a dedicated PLP or an signaling path. Inthis case, the RDT may be context information (static chain and/ordynamic chain) and/or signaling information including informationassociated with header compression. In some embodiments, the RDT shallbe transmitted whenever the context information is changed. In addition,in some embodiments, the RDT shall be transmitted every physical frame.In order to transmit the RDT every physical frame, the previous RDT maybe reused.

The receiver may select a first PLP and first acquire signalinginformation of the SLT, the RDT, the LMT, etc., prior to acquisition ofa packet stream. When signaling information is acquired, the receivermay combine the signaling information to acquire mapping betweenservice—IP information—context information—PLP. That is, the receivermay check which service is transmitted in which IP streams or which IPstreams are delivered in which PLP and acquire context information ofthe PLPs. The receiver may select and decode a PLP carrying a specificpacket stream. The adaptation module may parse context information andcombine the context information with the compressed packets. To thisend, the packet stream may be restored and delivered to the RoHCdecompressor. Thereafter, decompression may start. At this time, thereceiver may detect IR packets to start decompression from an initiallyreceived IR packet (mode 1), detect IR-DYN packets to startdecompression from an initially received IR-DYN packet (mode 2) or startdecompression from any compressed packet (mode 3).

Hereinafter, packet encapsulation will be described.

The link layer protocol may encapsulate all types of input packets suchas IP packets, TS packets, etc. into link layer packets. To this end,the physical layer processes only one packet format independently of theprotocol type of the network layer (here, an MPEG-2 TS packet isconsidered as a network layer packet). Each network layer packet orinput packet is modified into the payload of a generic link layerpacket.

In the packet encapsulation procedure, segmentation may be used. If thenetwork layer packet is too large to be processed in the physical layer,the network layer packet may be segmented into two or more segments. Thelink layer packet header may include fields for segmentation of thetransmission side and recombination of the reception side. Each segmentmay be encapsulated into the link layer packet in the same order as theoriginal location.

In the packet encapsulation procedure, concatenation may also be used.If the network layer packet is sufficiently small such that the payloadof the link layer packet includes several network layer packets,concatenation may be performed. The link layer packet header may includefields for performing concatenation. In concatenation, the input packetsmay be encapsulated into the payload of the link layer packet in thesame order as the original input order.

The link layer packet may include a header and a payload. The header mayinclude a base header, an additional header and/or an optional header.The additional header may be further added according to situation suchas concatenation or segmentation and the additional header may includefields suitable for situations. In addition, for delivery of theadditional information, the optional header may be further included.Each header structure may be pre-defined. As described above, if theinput packets are TS packets, a link layer header having packetsdifferent from the other packets may be used.

Hereinafter, link layer signaling will be described.

Link layer signaling may operate at a level lower than that of the IPlayer. The reception side may acquire link layer signaling faster thanIP level signaling of the LLS, the SLT, the SLS, etc. Accordingly, linklayer signaling may be acquired before session establishment.

Link layer signaling may include internal link layer signaling andexternal link layer signaling. Internal link layer signaling may besignaling information generated at the link layer. This includes theabove-described RDT or the below-described LMT. External link layersignaling may be signaling information received from an external module,an external protocol or a higher layer. The link layer may encapsulatelink layer signaling into a link layer packet and deliver the link layerpacket. A link layer packet structure (header structure) for link layersignaling may be defined and link layer signaling information may beencapsulated according to this structure.

FIG. 7 is a diagram showing a link mapping table (LMT) according to oneembodiment of the present invention.

The LMT may provide a list of higher layer sessions carried through thePLP. In addition, the LMT may provide additional information forprocessing link layer packets carrying the higher layer sessions. Inthis case, the higher layer session may also be referred to asmulticast. Information on IP streams or transport sessions transmittedthrough a specific PLP may be acquired through the LMT. In contrast,information on through which PLP a specific transport session isdelivered may be acquired.

The LMT may be delivered in any PLP identified as carrying LLS. In thiscase, the PLP in which the LLS is delivered may be identified by an LLSflag of L1 detail signaling information of a physical layer. The LLSflag may be a flag field indicating whether the LLS is delivered in thePLP, each PLP. In this case, L1 detail signaling information maycorrespond to the below-described PLS2 data.

That is, the LMT may be delivered in the same PLP along with the LLS.Each LMT shall describe mapping between PLPs and IP addresses/ports asdescribed above. As described above, the LLS may include an SLT and theIP address/port described in the LMT may be any IP address/portassociated with any service described in the SLT delivered in the samePLP as the LMT.

In some embodiments, the PLP identifier information in theabove-described SLT, SLS, etc. may be used to confirm informationindicating through which PLP a specific transport session indicated bythe SLT or SLS is transmitted may be confirmed.

In another embodiment, the PLP identifier information in theabove-described SLT, SLS, etc. will be omitted and PLP information ofthe specific transport session indicated by the SLT or SLS may beconfirmed by referring to the information in the LMT. In this case, thereceiver may combine the LMT and other IP level signaling information toidentify the PLP. Even in this embodiment, the PLP information in theSLT, SLS, etc. is not omitted and may remain in the SLT, SLS, etc.

The LMT according to the shown embodiment may include a signaling_typefield, a PLP_ID field, a num_session field and/or information on eachsession. Although the LMT of the shown embodiment describes IP streamstransmitted through one PLP, a PLP loop may be added to the LMT todescribe information on a plurality of PLPs in some embodiments. In thiscase, the LMT may describe, in a PLP loop, PLPs for any IP address/portassociated with any service described in the SLT delivered together, asdescribed above.

The signaling_type field may indicate the type of signaling informationdelivered by the table. The value of signaling_type field for the LMTmay be set to 0x01. The signaling_type field may be omitted. The PLP_IDfield may identify a target PLP to be described. If the PLP loop isused, each PLP_ID field may identify each target PLP. The PLP_ID fieldand subsequent fields thereof may be included in the PLP loop. Thebelow-described PLP ID field is an identifier for one PLP of the PLPloop and the below-described fields may be fields for the correspondingPLP.

The num_session field may indicate the number of higher layer sessionsdelivered through the PLP identified by the corresponding PLP_ID field.Information on each session may be included based on the numberindicated by the num_session field. This information may include asrc_IP_add field, a dst_IP_add field, a src_UDP_port field, adst_UDP_port field, an SID_flag field, a compressed_flag field, an SIDfield and/or a context_id field.

The src_IP_add field, the dst_IP_add field, the src_UDP_port field andthe dst_UDP_port field may indicate the source IP address, thedestination IP address, the source UDP port and the destination UDP portof the transport session among the higher layer sessions deliveredthrough the PLP identified by the corresponding PLP ID field.

The SID_flag field may indicate whether the link layer packet deliveringthe transport session has an SID field in the optional header. The linklayer packet delivering the higher layer session may have an SID fieldin the optional header and the SID field value may be equal to that ofthe SID field in the LMT.

The compressed_flag field may indicate whether header compression isapplied to the data of the link layer packet delivering the transportsession. In addition, presence/absence of the below-described context_idfield may be determined according to the value of this field. If headercompression is applied (compressed_flag=1), the RDT may be present andthe PLP ID field of the RDT may have the same value as the PLP_ID fieldassociated with this compressed_flag field.

The SID field may indicate the SIDs (sub stream IDs) of the link layerpackets delivering the transport session. These link layer packets mayinclude SIDs having the same values as this SID field in the optionalheader thereof. To this end, the receiver may filter link layer packetsusing LMT information and the SID information of the link layer packetheader, without parsing all link layer packets.

The context_id field may provide a reference for a context id (CID) inthe RDT. The CID information of the RDT may indicate the context ID ofthe compression IP packet stream. The RDT may provide contextinformation of the compression IP packet stream. Through this field, theRDT and the LMT may be associated.

In the above-described embodiments of the signaling information/table ofthe present invention, the fields, elements or attributes may be omittedor may be replaced with other fields. In some embodiments, additionalfields, elements or attributes may be added.

In one embodiment of the present invention, service components of oneservice may be delivered through a plurality of ROUTE sessions. In thiscase, an SLS may be acquired through bootstrap information of an SLT. AnS-TSID and an MPD may be referenced through the USBD of the SLS. TheS-TSID may describe not only the ROUTE session delivered by the SLS butalso transport session description information of another ROUTE sessioncarried by the service components. To this end, the service componentsdelivered through the plurality of ROUTE sessions may all be collected.This is similarly applicable to the case in which the service componentsof one service are delivered through a plurality of MMTP sessions. Forreference, one service component may be simultaneously used by theplurality of services.

In another embodiment of the present invention, the bootstrapping of anESG service may be performed by a broadcast or broadband network. Byacquiring the ESG over broadband, URL information of the SLT may beused. ESG information may be requested using this URL.

In another embodiment of the present invention, one service component ofone service may be delivered over the broadcast network and the otherservice component may be delivered over broadband (hybrid). The S-TSIDmay describe components delivered over the broadcast network such thatthe ROUTE client acquires desired service components. In addition, theUSBD may have base pattern information to describe which segments (whichcomponents) are delivered through which path. Accordingly, the receivermay confirm a segment to be requested from the broadband service and asegment to be detected in a broadcast stream.

In another embodiment of the present invention, scalable coding of aservice may be performed. The USBD may have all capability informationnecessary to render the service. For example, when one service isprovided in HD or UHD, the capability information of the USBD may havean “HD or UHD” value. The receiver may check which component isreproduced in order to render the UHD or HD service using the MPD.

In another embodiment of the present invention, through a TOI field ofthe LCT packets delivered through the LCT channel delivering the SLS,which SLS fragment is delivered using the LCT packets (USBD, S-TSID,MPD, etc.) may be identified.

In another embodiment of the present invention, app components to beused for app based enhancement/an app based service may be deliveredover the broadcast network as NRT components or may be delivered overbroadband. In addition, app signaling for app based enhancement may beperformed by an application signaling table (AST) delivered along withthe SLS. In addition, an event which is signaling for operation to beperformed by the app may be delivered in the form of an event messagetable (EMT) along with the SLS, may be signaled in the MPD or may bein-band signaled in the form of a box within DASH representation. TheAST, the EMT, etc. may be delivered over broadband. App basedenhancement, etc. may be provided using the collected app components andsuch signaling information.

In another embodiment of the present invention, a CAP message may beincluded and provided in the above-described LLS table for emergencyalert. Rich media content for emergency alert may also be provided. Richmedia may be signaled by a CAP message and, if rich media is present,the rich media may be provided as an EAS service signaled by the SLT.

In another embodiment of the present invention, linear servicecomponents may be delivered over the broadcast network according to theMMT protocol. In this case, NRT data (e.g., app components) of theservice may be delivered over the broadcast network according to theROUTE protocol. In addition, the data of the service may be deliveredover broadband. The receiver may access the MMTP session delivering theSLS using the bootstrap information of the SLT. The USBD of the SLSaccording to the MMT may reference the MP table such that the receiveracquires linear service components formatted into the MPU deliveredaccording to the MMT protocol. In addition, the USBD may furtherreference the S-TSID such that the receiver acquires NRT data deliveredaccording to the ROUTE protocol. In addition, the USBD may furtherreference the MPD to provide a reproduction description of datadelivered over broadband.

In another embodiment of the present invention, the receiver may deliverlocation URL information capable of acquiring a file content item (file,etc.) and/or a streaming component to a companion device through a websocket method. The application of the companion device may acquirecomponents, data, etc. through a request through HTTP GET using thisURL. In addition, the receiver may deliver information such as systemtime information, emergency alert information, etc. to the companiondevice.

FIG. 8 illustrates a configuration of a broadcast signal transmissionapparatus for future broadcast services according to an embodiment ofthe present invention.

The broadcast signal transmission apparatus for future broadcastservices according to the present embodiment may include an inputformatting block 1000, a bit interleaved coding & modulation (BICM)block 1010, a frame building block 1020, an OFDM generation block 1030and a signaling generation block 1040. Description will be given of anoperation of each block of the broadcast signal transmission apparatus.

In input data according to an embodiment of the present invention, IPstream/packets and MPEG2-TS may be main input formats, and other streamtypes are handled as general streams.

The input formatting block 1000 may demultiplex each input stream intoone or a plurality of data pipes, to each of which independent codingand modulation are applied. A DP is the basic unit for robustnesscontrol, which affects QoS. One or a plurality of services or servicecomponents may be carried by one DP. The DP is a logical channel in aphysical layer for delivering service data or related metadata capableof carrying one or a plurality of services or service components.

Since QoS depends on characteristics of a service provided by thebroadcast signal transmission apparatus for future broadcast servicesaccording to the embodiment of the present invention, data correspondingto respective services needs to be processed using different schemes.

The BICM block 1010 may include a processing block for a profile (orsystem) to which MIMO is not applied, and a processing block for aprofile (or system) to which MIMO is applied and may comprise aplurality blocks for processing each Data Pipe.

A processing block of the BICM block to which MIMO is not applied mayinclude a data FEC encoder, a bit interleaver, a constellation mapper, asignal space diversity (SSD) encoding block and a time interleaver. Aprocessing block of the BICM block to which MIMO is applied may isdistinguished from the processing block of the BICM block to which MIMOis not applied in that the processing block further includes a cell-worddemultiplexer and a MIMO encoding block

The data FEC encoder performs FEC encoding on an input BBF to generateFECBLOCK procedure using outer coding (BCH) and inner coding (LDPC). Theouter coding (BCH) is optional coding method. The bit interleaver mayinterleave outputs of the data FEC encoder to achieve optimizedperformance with a combination of LDPC codes and a modulation schemewhile providing an efficiently implementable structure. A detailedoperation of the bit interleaver will be described later. Theconstellation mapper may modulate each cell word from the bitinterleaver or the cell-word demultiplexer in the advanced profile usingeither QPSK, QAM-16, non-uniform QAM (NUQ-64, NUQ-256, or NUQ-1024) ornon-uniform constellation (NUC-16, NUC-64, NUC-256, or NUC-1024) mappingto give a power-normalized constellation point. This constellationmapping is applied only for DPs. It is observed that QAM-16 and NUQs aresquare shaped, while NUCs have arbitrary shapes. Both NUQs and NUCs aredefined specifically for each code rate and the particular one used issignaled by the parameter DP_MOD field in the PLS2 data. The timeinterleaver may operates at a DP level. Parameters of time interleaving(TI) may be set differently for each DP.

The time interleaver according to an embodiment of the present inventionmay be positioned between a BICM chain block and a frame builder. Inthis case, the time interleaver according to an embodiment of thepresent invention may use both a convolutional interleaver (CI) and ablock interleaver (BI) or selectively using either the CI or the BIaccording to a physical layer pipe (PLP) mode. A PLP according to anembodiment of the present invention is a physical path corresponding tothe same concept as that of the above-described DP, and a name of thePLP may be changed by a designer. A PLP mode according to an embodimentof the present invention may include a single PLP mode or a multi-PLPmode according to the number of PLPs processed by a broadcast signaltransmitter or a broadcast signal transmission apparatus. In the presentinvention, time interleaving in which different time interleavingschemes are applied according to PLP modes may be referred to as hybridtime interleaving.

The hybrid time interleaver may include a BI and a Cl. That is, whenPLP_NUM=1, the BI is not applied (BI is turned OFF) and only the CI isapplied. When PLP_NUM>1, both the BI and the CI may be applied (BI isturned ON). A structure and an operation of the CI applied whenPLP_NUM>1 may be different from a case of PLP_NUM=1. The hybrid timedeinterleaver may perform an operation corresponding to an inverseoperation of the hybrid time interleaver described above.

The cell-word demultiplexer is used for dividing a single cell-wordstream into dual cell-word streams for MIMO processing. The MIMOencoding block may process an output of the cell-word demultiplexerusing a MIMO encoding scheme. The MIMO encoding scheme of the presentinvention may be defined as full-rate spatial multiplexing (FR-SM) toprovide capacity increase with relatively small complexity increase atthe receiver side. MIMO processing is applied at the DP level. NUQ(e_(1,i) and e_(2,i)) corresponding to a pair of constellation mapperoutputs is fed to an input of a MIMO encoder and paired MIMO encoderoutput (g_(1,i) and g_(2,i)) is transmitted by the same carrier k andOFDM symbol I of respective TX antennas thereof.

The frame building block 1020 may map the data cells of the input DPsinto the OFDM symbols within a frame, and perform frequency interleavingfor frequency-domain diversity.

A frame according to an embodiment of the present invention is furtherdivided into a preamble, one or more frame signaling symbols (FSSs),normal data symbols. The preamble provides a set of basic transmissionparameters for efficient transmission and reception of a signal. And thepreamble indicates whether the emergency alert service (EAS) is providedin a current frame or not. A main purpose of the FSS is to carry PLSdata. For fast synchronization and channel estimation, and hence fastdecoding of PLS data, the FSS has a dense pilot pattern than a normaldata symbol.

The frame building block 1020 may include a delay compensation block foradjusting timing between DPs and corresponding PLS data to ensure thatthe DPs and the corresponding PLS data are co-timed at a transmitterside, a cell mapper for mapping PLS, DPs, auxiliary streams, dummycells, etc. to active carriers of the OFDM symbols in the frame and afrequency interleaver.

The frequency interleaver may randomly interleave data cells receivedfrom the cell mapper to provide frequency diversity. In addition, thefrequency interleaver may operate on data corresponding to an OFDMsymbol pair including two sequential OFDM symbols or an OFDM symbolusing a different interleaving-seed order to obtain maximum interleavinggain in a single frame.

The OFDM generation block 1030 modulates OFDM carriers by cells producedby the frame building block, inserts pilots, and produces a time domainsignal for transmission. In addition, this block subsequently insertsguard intervals, and applies peak-to-average power ratio (PAPR)reduction processing to produce a final RF signal.

The signaling generation block 1040 may create physical layer signalinginformation used for an operation of each functional block. Signalinginformation according to an embodiment of the present invention mayinclude PLS data. The PLS data includes PLS1 data and PLS2 data.

The PLS1 data is a first set of PLS data carried in an FSS symbol in aframe having a fixed size, coding and modulation, which carries basicinformation about the system in addition to the parameters needed todecode the PLS2 data. The PLS1 data provides basic transmissionparameters including parameters required to enable the reception anddecoding of the PLS2 data. In addition, the PLS1 data remains constantfor the duration of a frame group. The PLS2 data is a second set of PLSdata transmitted in an FSS symbol, which carries more detailed PLS dataabout the system and the DPs. The PLS2 contains parameters that providesufficient information for the receiver to decode a desired DP. The PLS2signaling further includes two types of parameters, PLS2 static data(PLS2-STAT data) and PLS2 dynamic data (PLS2-DYN data). The PLS2 staticdata is PLS2 data that remains static for the duration of a frame groupand the PLS2 dynamic data is PLS2 data that dynamically changes frame byframe.

PLS2 data may include FIC_flag information. A fast information channel(FIC) is a dedicated channel for carrying cross-layer information toenable fast service acquisition and channel scanning. FIC_FLAG is a1-bit field and indicates whether the FIC is used in a current frame. Ifthis field is set to ‘1’, the FIC is provided in the current frame. Ifthis field set to ‘0’, the FIC is not carried in the current frame. TheBICM block 1010 may include BICM block for protection of the PLS dataincluding a PLS FEC encoder, a bit interleaver and a constellationmapper.

The PLS FEC encoder may include a scrambler for scrambling PLS1 data andPLS2 data, a BCH encoding/zero insertion block for outer encoding on thescrambled PLS 1,2 data using a shortened BCH code for PLS protection,and insert zero bits after BCH encoding, an LDPC encoding block for LDPCencoding using an LDPC code and an LDPC parity puncturing block. The bitinterleaver may interleave each of shortened and punctured PLS1 data andPLS2 data. The constellation mapper may map the bit-interleaved PLS1data and PLS2 data to constellations.

The broadcast signal reception apparatus for future broadcast servicesaccording to the embodiment of the present invention may correspond tothe broadcast signal transmission apparatus for future broadcastservices described with reference to FIG. 8.

The broadcast signal reception apparatus for future broadcast servicesaccording to the embodiment of the present invention may include asynchronization & demodulation module carrying out demodulationcorresponding to a reverse procedure of a procedure performed by thebroadcast signal transmission apparatus, a frame parsing module parsinginput signal frames and extracting data through which a service selectedby a user is transmitted, a demapping & decoding module which convertinput signals into bit domain data and then deinterleave the same asnecessary, perform demapping of mapping applied for transmissionefficiency and correct an error generated on a transmission channelthrough decoding, an output processor performing reverse procedures ofvarious compression/signal processing procedures which are applied bythe broadcast signal transmission apparatus and a signaling decodingmodule obtaining PLS information from a signal demodulated by thesynchronization & demodulation module. The frame parsing module, thedemapping & decoding module, and the output processor may executefunctions thereof using data output from the signaling decoding module.

The time interleaver is described below. Each TI group according to anembodiment of the present invention is either mapped directly to oneframe or spread over P_(I) frames. Each TI group is also divided intomore than one TI block (N_(TI)), where each TI block corresponds to oneusage of a time interleaver memory. The TI blocks within the TI groupmay contain slightly different numbers of XFECBLOCKs. Typically, thetime interleaver may also function as a buffer for DP data prior to aprocess of frame building.

The Time interleaving according to an embodiment of the presentinvention is a twisted row-column block interleaver. The twistedrow-column block interleaver according to an embodiment of the presentinvention may column-wise write a first XFECBLOCK into a first column ofa TI memory, a second XFECBLOCK into a next column, and may write theremaining XFECBLOCKs within the time interleaving block. Then, in theinterleaving array, cells are diagonal-wise read diagonal-wise from afirst row (rightwards along a row beginning with a left-most column) toa last row, N_(r) cells are read out. Moreover, in order to achievesingle-memory deinterleaving on the receiver side regardless of a numberof XFECBLOCKs in a TI block the twisted row-column block interleaver mayinsert the virtual XFECBLOCKs into the TI memory. The virtual XFECBLOCKsmust be inserted in front of other FECBLOCKS to achieve single-memorydeinterleaving on the receiver side.

FIG. 9 illustrates a write operation of a time interleaver according toan embodiment of the present invention.

A left block in the figure illustrates a TI memory address array, andright blocks in the figure illustrate a write operation when two virtualFEC blocks and one virtual FEC block are inserted into heads of twocontiguous TI groups, respectively.

The frequency interleaver according to the present embodiment mayinclude an interleaving address generator for generating an interleavingaddress for applying corresponding data to a symbol pair.

FIG. 10 illustrates an interleaving address generator including a mainpseudo-random binary sequence (PRBS) generator and a sub-PRBS generatoraccording to each FFT mode which are included in a frequency interleaveraccording to an embodiment of the present invention.

(a) shows the block diagrams of the interleaving-address generator for8K FFT mode, (b) shows the block diagrams of the interleaving-addressgenerator for 16K FFT mode, and (c) shows the block diagrams of theinterleaving-address generator for 32K FFT mode.

The interleaving process for the OFDM symbol pair is described asfollows, exploiting a single interleaving-sequence. First, availabledata cells (the output cells from the cell mapper) to be interleaved inone OFDM symbol O_(m,l) is defined as O_(m,l)=[x_(m,l,0), . . . ,x_(m,l,p), . . . , x_(m,l,Ndata−1)] for l=0, . . . , N_(sym)−1, wherex_(m,l,p) is the p^(th) cell of the l^(th) OFDM symbol in the m^(th)frame and N_(data) is the number of data cells: N_(data)=C_(FSS) for theframe signaling symbol(s), N_(data)=C_(data) for the normal data, andN_(data)=C_(FES) for the frame edge symbol. In addition, the interleaveddata cells are defined as P_(m,l)=[v_(m,l,0), . . . , v_(m,l,Ndata−1)]for l=0, . . . , N_(sym)−1.

For the OFDM symbol pair, the interleaved OFDM symbol pair is given byv_(m,l,Hl(p))=x_(m,l,p), p=0, . . . , N_(data)−1, for the first OFDMsymbol of each pair v_(m,l,p)=x_(m,l,Hl(p)), p=0, . . . , N_(data)−1 forthe second OFDM symbol of each pair, where H_(l)(p) is the interleavingaddress generated based on a PRBS generator and a cyclic shift value(symbol offset) of a sub-PRBS generator.

Hereinafter, an app signaling method according to an embodiment of thepresent invention is described below.

An app-based service means a service including app-base features thatprovide a user interface for the service.

In this specification, the application may be called an app. In thepresent invention, an app may be a downloaded app or a native app. Thedownloaded app may mean a collection of downloaded documents thatconstruct a function, such as interactivity or targeted ad insertion.The documents may include HTML, JavaScript, CSS, XML and multimediafiles. The app may access data other than the part of its app. Thenative app may mean software built in a receiver so that it can performa function of downloading data, such as electronic service guide (ESG)or emergency alerting (EA).

The service may include at least one app-based enhancement. For example,a linear service may include an app-based enhancement. The app-basedenhancement may include an app that is driven in the background and thatmanages target ad insertion. Furthermore, the linear service may includean app-based enhancement including a collection of apps to provideinteractive watching experiences that enhance an audio/video program.Each app-based enhancement is separately signaled. Accordingly, creatorsof various apps do not need to coordinate their signaling.

The collection of apps that construct the app-based enhancement may besignaled by XML document. An embodiment of the XML document is describedbelow.

FIG. 11 shows an application signaling table according to an embodimentof the present invention.

Service signaling information may include an app signaling table (AST),such as an embodiment of FIG. 11. The AST has been divided into FIGS.11a, 11b and 11c and shown, but may be signaled as one table.

The AST may include signaling information about each of app-basedenhancements included in a service. A service or service signalinginformation may include at least one AST. The AST may not include all ofelements shown in FIG. 11. That is, the AST includes at least elementshown in the embodiment of FIG. 11. A broadcaster may control theoperation of an app according to a broadcast service using an AST.

A description of each of the elements included in the AST of FIG. 11 isas follows.

ApplicationList: include a list of application elements

Application: include the properties of an application

appName: the name of an application

@language: the language of an appName element

applicationIdentifier: identify an application

orgiD: a globally unique value to identify an organization responsiblefor an application

apppID: a value to identify an application allocated by an organizationspecified by orgID. It may be unique in the scope of an organizationspecified by orgID

applicationDescriptor: include the general properties of an app

type: identify a related type of an app so that a receiver can be awareof whether the app is supported

atsc:AtscApp: may be present in the AST. It may have a value indicativeof ATSC 3.0 application, and the value indicative of ATSC 3.0application may be the value of “ATSC3-HTML”, for example.

controlCode: indicate the life cycle state of an application. Anembodiment of control code is the same as FIG. 12.

visibility: indicates whether a consent request of the launching of anapp is visible with respect to a user and/or another application thatpasses through an application listing API. It may be “VISIBLE ALL.”

serviceBound: indicate whether an application is bound to a service.True: broadcast-related app, false: broadcast-independent app

priority: indicate related priority of an app. “FFFF” may correspond toan emergency alert (EA) app.

version: indicate the version number of an app

icon: shall not be present

storageCapabilities: include the properties of a storable app

storageProperty: shall not be present

@launchableFromBroadcast: indicate whether an app can be usefullylaunched before it is fully cashed

@launchableCompletelyFromCache: indicates whether a connection with atransport protocol has been requested

@launchableWithOlderVersion: indicates whether a longer cashed versionof an app is executed although a higher version is signaled in broadcast

ApplicationUsage: identify whether an app provides a specific,well-known function. An embodiment of the value of this element is shownin FIG. 13

applicationBoudary: include a set of boundaries of an app

BoundaryExtension: an URL prefix to describe data elements thatconstruct an app. Specific URLs matched with this prefix are taken intoconsideration within an app boundary. The URL prefix may be a strictprefix starting from “http:”, “https:”, “ftp:”, “tag:” or “file:.” Onlyprefixes to construct at least one second level domain may be supported.Path elements may be overridden.

applicationTransport: may identify a transport protocol associated witha service component and provide protocol dependency information

URLBase: the first part of an HHTP URL that confirms HTTP1.0 or thefirst part of an HTTPS ULR that confirms RFC2818 or the first part ofanother URL that confirms RFC 3986

URLExtension: the later part of an HHTP URL that confirms HTTP1.0 or thelater part of an HTTPS ULR that confirms RFC2818 or the URL of a schemesupported by a registered interaction channel transport service provider

atsc: RouteSessionInto: the parameter of an ROUTE session that carriescontent items related to this app, if present

LCTSession: the parameter of an LST session including the part of theROUTE session

@tsi: the transport session identifier of an LCT session

@plpID: the PLP identifier of an PLP including an LCT session (default:the PLP ID of the ROUTE session including an LCT session)

@broadcastStreamID: the identifier of a broadcast stream (default: acurrent broadcast stream)

@plpID: the PLP ID of a default PLP for an LST session within the ROUTEsession. This plpID information may be overridden by the PLP ID of anindividual LCT session. (default: a PLP including the AST)

@sourceIpAddress: dotted-IPv4 source address information of packetswithin the ROUTE session. (default: the source IP address of a packetincluding the AST)

@destinationIpAddress: dotted-IPv4 destination address information of apacket within the ROUTE session. (default: the destination IP address ofa packet including the AST)

@destinationPort: the port number of packets within the ROUTE session(default: the destination port of packets including the AST)

applicationLocation: the URL path component of the entry point documentof an app

applicationSpecificDescriptor: include a specific descriptor dependenton the type of an app. It may include an externally defined descriptor.

atsc:atscDescriptor

size: A total size (bytes) of an app

requiredCapabilities: device capabilities meaning the rendition of anapp (as defined in A/332 “service announcement”). That is, it mayindicate device capabilities necessary for the smooth execution andpresentation of this app.

icon: include the properties of an icon indicative of an app

@filename: indicate the file name of the icon. It may be related to thebase part of a URL within applicationTransport

@size: indicate the size of the icon in a pixel number. In anembodiment, values, such as “24×32”, “32×32”, “48×64”, “64×64”,“96×128”, “128×128”, “192×256” and “256×256”, may be used.

@aspectRatio: indicate a pixel aspect ratio. In an embodiment, values,such as “1_1”, “4_3” and “16_9”, may be used.

ApplicationRecordingDescriptor: include extra information about an applife cycle if a program is recorded.

scheduled_recording_flag: indicates whether an application is suitablefor recording if a service signaled by scheduled recording is recorded.

trick_mode_aware_flag: indicate whether an app is trick-mode aware

time_shift_flag: indicates whether an app is suitable for recording if asignaled service is recorded in a time-switch recording mode.

dynamic_flag: indicates whether an app depends on the use of dynamicdata from broadcast that is being executed

av_synced_flag: indicates whether an app requests the use of streamevents

initiating_replay_flag: when it is set to 1, a terminal does notinitiate the playback of a stream located in the same recording as anapp. The app is responsible for the start of the playback. When it isset to 0, it starts an app as usual and initiates the playback. Thisflag is taken into consideration only when the playback of recording isfirst started. After this point, the value of this flag is overridden.

storage_properties: indicate the storage importance of a labeled part ofan app. In an embodiment, they are not stored if it is “0”. It indicatesthat storage is very critical if it is “1” and indicates that storage isoptional if it is “2.” “3”˜“255” may be reserved for future use.

timeSlotInfo: the time interval of the type of time slot(acquisition/presentation) of an app. This element may refer to a timeslot descriptor defined by Section 8.7 (“Time Slot Descriptor”) of A/103“Not-Real-Time Content Delivery.”

timeslot_type: indicate the type of time slot. In an embodiment, “0”indicates an acquisition slot, “1” indicates a presentation slot, and“2”˜“255” may be reserved for future use.

timeslot_start: the number of GPS seconds after UTC 00:00:00 Jan. 6,1980 and indicates the start time of a time slot. The value of 0indicates that the time slot has started in the indefinite past.

timeslot_length: indicate the length of a time slot in a minute unit

acquitision_time: indicate a minimum time interval length necessary toguarantee that one complete instance of an app is transmitted during atime interval in a minute unit. The time interval is assumed to start ata specific time during the time slot, including the end of the timeslot.

repeat_period: indicate the repetition period of a time slot in a minuteunit

contentLinkage: the EFDT indication number of an app

contentItem: a file consumed by an app. This element refers to thesyntax and concept of a content item defined in Section 6.3“Non-Real-Time Information Table” and Section 4.2 “Content Item Concept”of A/103 “Not-Real-Time Content Delivery.”

@location: the URL of a content item

@contentLinkage: the EFDT indication number of a content item

@updatesAvailable: indicates whether a content item will be periodicallyupdated

@size: a content item indicates the size in bytes

timeSlotInfo: a time interval for the type of a time slot(acquisition/presentation) for a content item. This element may refer toa time slot descriptor defined by Section 8.7 (“Time Slot Descriptor”)of A/103 “Not-Real-Time Content Delivery.”

timeslot type: indicate the type of a time slot. In an embodiment, “0”indicates an acquisition slot, and “1” indicates a presentation slot.“2”˜“255” may be reserved for future use.

timeslot_start: the number of GPS seconds after UTC 00:00:00 Jan. 6,1980 and indicates the start time of a time slot. The value of 0indicates that the time slot has started in the indefinite past.

timeslot_length: indicate the length of a time slot in a minute unit.

acquitision_time: indicate a minimum time interval length necessary toguarantee that one complete instance of an app is transmitted during atime interval in a minute unit. The time interval is assumed to start ata specific time during the time slot, including the end of the timeslot.

repeat_period: indicate the repetition period of a time slot in a minuteunit

graphicConstraintsDescriptor: a graphic restriction descriptor

can_run_without_visible_ui: indicates whether an app requires UI display

handles_configuration_changed: indicates whether an app can handle achange in a graphic restriction

handles_externally_controlled_video: indicates whether an app can beusefully executed if the presentation of video is under the control of asecond app outside a service

graphics_configuration_byte: indicate a supported graphic configuration.In an embodiment, it may indicate the following information depending ona value.

0: reserved

1: full screen standard definition

2: full screen 960×540

3: full screen 1280×720

4: full screen 1920×1080

5-31: reserved for the future use of ATSC

32-255: reserved for future use

screenPosition: indicate a screen position where an app is displayed. Itmay provide two positions of a top-left corner and bottom-right cornerof display. An embodiment of syntax may be expressed as “x1_y1_x2_y2” ifthe two positions are (x1, y1) and (x2, y2). “FULL” indicates that anapp is displayed on a full screen.

ApplicationReference: shall not be present

FIG. 12 shows an application control code according to an embodiment ofthe present invention.

A description of an identifier is as follows.

AUTOSTART: an app needs to be started when a service is selected exceptthat the app is already executed

PRESENT: the execution of an app is permitted when a service isselected, but the app does not automatically starts when the service isselected

KILL: an app must be stopped as soon as possible

DISABLED: an app should not start, and fails if it starts

SUSPEND: an app must be suspended as soon as possible

FIG. 13 is an embodiment of an app use type according to the presentinvention.

A description of ApplicationUsage values is as follows.

urn:dvb:mhp:2009:digitalText: digital text application

urn:atsc:3:esg: electronic service guide

urn:atsc:3:eas: emergency alert service (rich media)

urn:atsc:3:tai: target ad insertion

FIG. 14 shows an application lifetime table (ALT) according to anotherembodiment of the present invention.

In an embodiment, information about the life cycle of an application inthe AST may be separately delivered. This is for the information aboutthe life cycle specified in a control code (controlcode) element toprovide a more efficient transmission method by taking intoconsideration that the information is more frequently changed than otherpieces of information within the AST. For example, the information aboutthe life cycle may be provided as in FIG. 14, and a description ofelements included in the information is as follows.

ApplicationList: include a list of application elements.

Application: include the properties of an application.

appNAme: the name of the application

@language: the language of an appName element

applicationIdentifier: identify the application

orgID: a globally unique value to identify an organization responsiblefor the application

apppID: a value to identify the application assigned by an organizationspecified by orgID. It may be unique in the scope of the organizationspecified by orgID.

application Descriptor: include the general properties of the app

type: identify a related type of app so that a receiver can be aware ofwhether the app is supported. That is, it identify the type of app sothat a receiver can be aware of whether the app can be normallyexecuted.

atsc:AtsdApp: it may be present in the AST. It may have a valueindicative of an ATSC 3.0 application. In an embodiment, the valueindicative of ATSC 3.0 may have a value of “ATSC3-HTML.”

controlCode: indicate the life cycle state of the application. Anembodiment of the control code is shown in FIG. 12.

FIGS. 15 and 16 show the life cycle state of an application and thetransition of states according to an embodiment of the presentinvention.

FIG. 15 shows app life cycle states according to identifiers. Meaningsaccording to the identifiers are as follows.

Active: an app is being executed

Suspended: temporarily suspended from execution, and the state thereofis stored

Released: not active/suspended

Ready): downloaded and prepared for execution, but not yet executed.

FIG. 16 shows the state transition of an application.

An app may switch from the ready state to the active state in responseto a user selection or “AUTOSTART” of the AST. AUTOSTART may switch tothe active state when an app of higher priority is not executed or the“KILL” setting of a user is not present. An app may switch to theReleased state in response to an AST “DISABLED” command or turn away.

An app may switch from the active state to the suspended state by the“SUSPEND”/other app activated/turn away of the AST. Furthermore, the appmay switch from the active state to the released state by the “KILL” ofa user or the “KILL” of the AST.

An app may switch from the suspended state to the active state by the“AUTOSTART” or Tune To of the AST or if an app of other higher priorityis not executed or if there is no “KILL” setting of a user. The app mayswitch to the released state by the “KILL” command of the AST or after aspecific time. Specific duration may be changed depending on a receiverimplementation.

An app may switch from the released state to the active state by the“AUTOSTART” or Tune To command of the AST. AUTOSTART may switch from thereleased state to the active state if an app of higher priority is notexecuted or if there is no “KILL” setting of a user. Furthermore, theapp may switch to the ready state in response to the “PRESENT” or TuneTo of the AST.

The AST for the aforementioned app enhancement may be transmitted to abroadcast network. The AST may be transmitted to a service layersignaling channel. In other words, the AST may be included in SLSinformation and transmitted or may be referred by the SLS informationand transmitted.

The AST may be delivered in a broadband. In such a case, the AST may betransmitted through an HTTP request using base URL information signaledby the SLT for a service. Such URL information may be redistributedthrough audio/video watermark.

Timing and location for the scheduled update of the AST may be providedby validUntil and nextURL properties within the metadata wrapper of theAST. The availability of an unscheduled update may be asynchronouslysignaled through a dynamic event.

A signaling method using a video/audio watermark is described below.

The video element of a broadcast program may be encoded into a datastream that may be recovered from uncompressed video in a receiver. Thebroadcast receiver that receives the video may use the data stream forvarious purposes. In an embodiment, the various purposes include thehybrid (broadband) delivery of program elements necessary to supportfunctions, such as interactivity, dynamic ad insertion, service usemonitoring, and content identification.

In this specification, a video watermarking technology is to modulatethe luma component of video within the first 2 lines of each videoframe. Two encoding options may be used. A 1x version method ofproviding a watermark payload of 30 bytes per frame and a 2x versionmethod of providing a twice capacity may be provided. In an embodiment,a broadcast receiver may not display a corresponding video because it isaware that the first 2 lines of the video include a watermark. Luma(luminance) has information about the brightness difference of an image.In an embodiment of the present invention, a 1X emission format may use30 bytes per video frame, and a 1X emission format may use 60 bytes pervideo frame. Furthermore, a VP1 message may be used as a video watermarkpayload. If the

VP1 (viewpoint 1) message is used, the VP1 message may be repeated overmultiple video frames. If a watermark payload is not recovered from anindividual video frame, a receiver may recover a VP1 message from two ormore contiguous video frames by combining luma values. VP1 indicates awatermarking technology.

FIG. 17 shows a video watermark payload according to an embodiment ofthe present invention.

The payload format of a video watermark may be the same in a 1X systemand a 2X system. A description of fields (information) of the watermarkpayload of FIG. 17 is as follows.

run_in_pattern: it is a 16-bit value and identify a video line includinga watermark of a specific format

wm_message_block: a fragment of wm_message( ) greater than a watermarkmessage of a full wm_message( ) or less

zero_pad: a value of zero used to be padded to the end of a frame

FIG. 18 shows a watermark message according to an embodiment of thepresent invention.

Watermark message blocks may have syntax, such as FIG. 18. A descriptionof fields (information) included in the message of FIG. 18 is asfollows.

wm_message_id: a value of 8 bits to identify data carried in a messageblock. An embodiment of a watermark message identified by an id is shownin FIG. 19. A video watermark message may include at least one watermarkmessage corresponding to a watermark message ID.

wm_message_block_length: indicate the number of remaining bytes ofwm_message_block that includes a CRC32 field from a field right afterthis field.

wm_message_version: this field may be included in a watermark messageblock although not shown in FIG. 18. The value of this field may beincreased when wm_message information is changed. A receiver may discarda duplicated message using this field. The reason for this is that avideo signal may include the same watermark message repeated toguarantee reliability of delivery.

fragment number: it is a 2-bit value and may indicate a value obtainedby subtracting 1 from a current message fragment. For example, when thevalue of this field is “00”, it indicates that a watermark message isthe first fragment of the entire message. When the field value is “01”,it indicates a watermark message carries the second fragment of theentire message.

last_fragment: indicate the fragment number of the last fragment thatdelivers a complete watermark message.

wm_message_bytes( ) when the value of the last fragment field(last_fragment) is 0, wm_message_bytes( ) may become the completeinstance of a watermark message identified by watermark message ID(wm_message_id) information. When the value of the last fragment field(last fragment) is not 0, wm_message_bytes( ) may become the fragment ofa watermark message identified by watermark message ID (wm_message_id)information.

message_crc_32: if a message is transmitted in two or more fragments,32-bit CRC that covers the message may be provided in the last fragment.If a message is not a fragmented message, a message CRC 32 field may notbe present.

CRC_32: a 32-bit field including a CRC value that provides the zerooutput of a register within a decoder

FIG. 19 shows the type of message according to the identifier of awatermark message according to an embodiment of the present invention.

As in FIG. 19, the value of a video watermark message according to eachid value is as follows.

0x00: reserved

0x01: a content identifier (ID) message (content_id_message( ))

0x02: a presentation time message (presentation_time_message( ))

0x03: a URI message (uri_message( ))

0x04: a VP1 message (vp1_messages))

0x05: a dynamic event message (dynamic_event_message( ))

0x06: an emergency alert message (emergency_alert_message( ))

0x07: a display override message (display_override_message( ))

0x08-0x7F: reserved

0x80-0xFF: user private

The content ID message delivers a content ID associated with a programand a major/minor channel number associated with a service. The contentID message is not transmitted in fragments.

The presentation time message may be carried within one watermarkpayload. The presentation time message indicates the presentation timeof a video frame that carries a watermark. The presentation time messagemay include presentation time information indicative of the presentationtime of a frame associated with a watermark and presentation time msinformation (presentation_time_ms) indicative of an offset of amillisecond unit from the time indicated by the presentation timeinformation.

The URI message may deliver various types of URIs. The URI message maybe transmitted as fragments. The URI message may include URI typeinformation. The URI type information may indicate a URL type, such as asignaling server, an ESG data server, a service usage data gatheringreport (SUDGR) server, a dynamic event HTTP server or a dynamic eventweb socket server, depending on its value,

The VP1 message may enable a recovery process along with a videowatermark. If present, the VP1 message may be the first watermarkmessage present in a video frame. If present, a VP1 message that carriesthe same data may be repeated with respect to a plurality of contiguousvideo frames.

The dynamic event message (dynamic_event_message) and display overridemessage are described with reference to the following drawing.

FIG. 20 shows a dynamic event message according to an embodiment of thepresent invention.

The dynamic event message (dynamic_event_message) supports dynamic eventdelivery within a video watermark. A description of pieces ofinformation included in the dynamic event message of FIG. 20 is asfollows.

delivery_protocol_type: indicate the delivery protocol of a service towhich a dynamic event may be applied. The delivery protocol may be anROUTE/DASH protocol or an MMT protocol (MMTP).

scheme_id_uri_length: indicate the length of a scheme ID URI string(scheme_id_uri_length) field.

scheme_id_uri_string: provide scheme UD URI (schemeIdUri) informationabout the event stream of an event.

value_length: indicate the length of a value string (value_string)field.

value_string: indicate the value of the event stream of an event.

timescale: indicate the time scale of the event stream of an event. Thetime scale may be used in a duration field.

presentation_time: indicate the presentation time of an event.

presentation_time_ms: indicate an offset of a millisecond unit from thetime indicated by presentation time information. An actual presentationtime of a millisecond unit may be indicated using presentation time(presentation_time) information and presentation time millisecond(presentation_time_ms) information.

In order for the presentation time information to be meaningful for aROUTE/DASH service, MPD@suggestedPresentationTime information may bepresent in a DASH MPD.

duration: indicate the duration of an event in the time scale.

id: indicate the ID of an event. The ID of an event may be unique withinan event stream.

data_length: indicate the length of a data field.

data: include data necessary to correspond to an event. A format thereofand the use of this data may be include in an event streamspecification.

FIG. 21 shows a display override message according to an embodiment ofthe present invention.

FIG. 21 shows an embodiment of a display override message signaled in avideo watermark.

The display override message may indicate that a receiver should outputa source broadcast video and source broadcast audio without specificoverlaid graphic or any obstruction. When the display override messageis received, a receiver may suspend a specific app that provides textand graphic on a screen, and may terminate specific replacement content,such as insertion.

overide_duration: the override duration field may indicate duration forwhich override must continue after a message is received. When the valueof override duration information is “0”, override may be immediatelyterminated.

An audio watermark payload is described below.

The audio watermark may be added to an audio segment by a watermarkembedder. For example, the watermark embedder may receive payload dataand an audio segment and output an audio segment including a watermark.In this specification, a watermark payload may be added to audio using aVP1 audio watermark technology. An output audio segment may provide areceiver with payload information through a VP1 watermark. VP1 means astandardized watermarking technology of an ATSC audio watermark emissionspecification. A VP1 payload may include domain type information, aserver field, an interval field and a query flag.

A VP1 audio watermark is co-resident with audio energy within the regionof an audio frequency spectrum including a perceptually importantcomponent. In a receiver, a watermark extractor may extract payload datafrom received audio.

An audio watermark payload may be transmitted in a packet structure. Thepacket of an audio watermark may include scrambled parity(scrambled_parity) information and scrambled payload (scrambled_payload)information. The scrambled payload information may be scrambled VP1payload (scrambled_vp1_payload) information. A VP1 payload may be calleda watermark payload.

FIG. 22 shows an audio watermark payload according to an embodiment ofthe present invention.

An audio watermark payload, that is, a VP1 payload, may include domaintype information, small domain information (small_domain) and largedomain (large_domain) information. The domain type information indicateswhether payload information is for a small domain or for a large domain.The small domain means the division of a payload having an intervalfield of a 17-bit size, which is sufficient to support watermarking ofcontent of about 54 hours. The large domain means the division of apayload having an interval field of a 25-bit size, which is sufficientto support watermarking of content of about 1 year and 7 months.

FIG. 23 shows (a) small domain information and (b) large domaininformation included in an audio watermark payload.

As in FIG. 23, each of small domain information and large domaininformation may include server field (server_field) information,interval field (interval_field) information, and query flag (query_flag)information.

The server field (server_field) information may include a server code.

The interval field (interval_field) information may include an intervalcode.

The query flag (query_flag) field may be signaled when a dynamic eventis available. A change of this field value between the contiguouswatermark payloads within a watermark segment indicates that a dynamicevent is available from a dynamic event HTTP server.

In the case of a small domain, the range of the value of a server codemay be 00000000˜7FFFFFFF (hexadecimal), and the range of an intervalcode value may be 00000000˜0001FFFF (hexadecimal). In the case of alarge domain, the range of the value of a server code may be00000000˜007FFFFF (hexadecimal), and the range of an interval code valuemay be 00000000˜01FFFFFF (hexadecimal).

In an embodiment, an interval code of all of “1s” may be used as asignal that instructs a receiver to immediately stop all of graphicoverlays and/or substitute content. The interval code is not used totransmit a request to a remote server. The interval code having the “1s”may be used as the aforementioned display override information. In thiscase, the interval code having 1s may be called a display overrideindicator. In other words, an audio watermark payload may include orcarry a display override indicator.

In the case of a small domain watermark type, the interval code of adisplay override indicator may include 17 contiguous 1s. In the case ofa large domain watermark type, the interval code of a display overrideindicator may include 25 contiguous 1s.

The interval code values may be used to instruct a receiver toimmediately stop graphic overlay or substitute content and toexclusively display unaltered content from a broadcast stream. Theinterval code values do not have a meaning as a media timeline timebase.

The use of the interval code may be orthogonal to the value of theserver code. The server code may be set to indicate that a broadcaststream is displayed as unusual.

An audio watermark segment is the contiguously marked interval ofcontent, including a VP1 payload within contiguous cells having the sameserver code and a sequentially incrementing interval code. A query flagmay be changed between contiguous VP1 payloads within the audiowatermark segment. The audio watermark segment may include VP1 payloadswithin contiguous cells having the same server code and a sequentiallyincrementing interval code.

The recovery process of a receiver is described below. Redistributionsetting means a situation in which audio/video TV content without directaccess to a broadcast stream. The recovery process means a process for areceiver to obtain supplementary content provided by the broadcaster ofcontent that is being received in broadband by accessing thesupplementary content.

When a receiver receives an audio watermark included in the content orreceives a VP1 message included in a video watermark, it may perform arecovery process. When a full set of video watermarks is received inreceiving content, a device may perform another recovery process.

Watermark-based signaling acquisition processing through a broadbandstarted from a VP1 message included in an audio watermark or videowatermark may be performed as follows.

The receiver may recover a VP1 payload from the audio or videowatermark. Furthermore, a receiver may form a URL for a request usingthe domain type, server field and interval field of the VP1 payload, andmay transmit an HTTP request to a recovery file server using the URL.

The receiver may receive a recovery file as a response to the request.The recovery file may include the original presentation time of contentinformation about a service that is being watched, and a URL used toretrieve a set of signaling files necessary for the access andpresenting of supplementary content at the start of the VP1 payload.

The receiver may recover the following set of signaling files using theURLs of a recovery file.

an MPD for a ROUTE/DASH service and MMPT services and ROUTE/DASDservices having available additional streaming content through theInternet

an AST for services including an available app-based feature through theInternet

an AEI for MMT services

an MPT for MMT services

A receiver may obtain and provide supplementary content using asignaling file. The receiver may synchronize the supplementary contentand audio/video using timing information of a recovery file.

The query flag of a VP1 payload may be used to signal the availabilityof an event. When the query flag is detected, a receiver may request anevent.

A recovery file, a dynamic event and signaling files may be delivered asa multi-part multipurpose Internet mail extensions (MIME) messageencapsulated as a multimedia broadcast/multicast service (MBMS) metadataenvelope. The multi-part MIME message encapsulated as the MBMS metadataenvelope includes a valid from attribute, a valid until attribute, and anext URL (“next URL”) attribute. The valid from attribute and the validuntil attribute define the valid interval of a signaling file, and thenext URL attribute defines the URL of a next scheduled version of asignaling file. Accordingly, a device may perform the scheduled updateof a required signaling file.

This event may be used to signal the execution of an app or theavailability of the scheduled update of a signaling file in a runtimeenvironment. In the former case, a receiver may transfer an event to aregistered app so that the event is executed. In the latter case, anevent includes the URL of an updated signaling file, and a receiver mayretrieve the signaling file.

If an audio watermark disappears, a receiver may terminate thepresentation of specific supplementary content. In this case, a receivermay recognize the disappearance of the watermark as “turn away” to a newservice that does not support specific supplementary content.

If the server field of an audio watermark is changed or an intervalfield has discontinuity, a receiver may terminate the presentation ofspecific supplementary content and restart signaling acquisition.

In the case of a ROUTE/DASH-based service, the original presentationtime within the recovery file of content at the start of a watermark maybe associated with the media presentation time of the current MPD of aservice. In the case of an MMT-based service, the original presentationtime within the recovery file of content at the start of a watermark maybe an NPT time.

A signaling acquisition method based on the aforementioned audiowatermark may be applied to a signaling acquisition method based on avideo watermark within a common range.

FIG. 24 shows a recovery file format according to an embodiment of thepresent invention.

A receiver may transmit a recovery data request to a recovery server.The receiver may transmit the recovery data request by issuing an HTTPGET or HTTP GET request with respect to a resource specified by a URLconfigured from a VP1 payload. In the HTTP request, a host name may bedetermined based on the domain type of a VP1 watermark code.

A recovery file format may be a JSON document. A unique recovery filemay be present in each VP1 payload. A description of elements/attributesin the recovery file of FIG. 24 is as follows.

ThisComponent: a media component in which a watermark including a VP1payload having a server code and an interval code has been embedded

serverCode: provide a server code value used in a query request (HTTPrequest) in which a recovery data table is provided as a response

intervalCode: provide an interval code value used in a query request(HTTP request) in which a recovery data table is provided as a response

ComponentDescription: a data element that describes ThisCompomentprovided in FIG. 25

querySpread: indicate maximum duration that delays the submission of adynamic event HTTP request. If this field is signaled by a query flag ina VP1 payload, time of a millisecond unit that randomly selects time toquery a dynamic event server.

OtherComponent: describe a watermark media component associated with thesame service as ThisCompoment. It indicates audio or video componentsdifferent from this component that carries a coincident VP1 payload.

ContentIDList: a content ID list

ContentID: a content identifier.

type:—the type of ContentId, and this value may indicate “EIDR” or“Ad-ID.”

“EIDR” indicate a content identification per EIDR registry

“Ad-ID” indicates a content identifier per Ad-ID registry

cid: may include an EIDR or Ad-ID string. The type of content identifiermay be given by the type attribute of ContentID.

validFrom: provide information about when a content ID is valid.

validUntil: provide information about how long will a content ID isvalid

SourceID: indicate a distribution source that may be provided bywatermark content

ATSCSourceID: indicate a distribution source that adopts an ATSCemission specification,

country: a country code associated with a primary administrative entityto which a broadcast stream ID (BSID) has been assigned

bsid: the BSID of an ATSC distribution source.

majorChannelNo: the major channel number of a service

minorChannelNo: the minor channel number of a service

Service: indicate a service that signals a format and broadband location

serviceId: an identifier (16-bit integer) uniquely identifying thisservice within a broadcast area

sltSvcSeqNum: indicate the sequence number of SLT service informationhaving the same service ID as service ID properties. The value of SLTservice sequence number (sltSvcSeqNum) information for each service maybe increased by 1 if there is a change of a service element. If a changeis not present, the value of sltSvcSeqNum is not increased. When thevalue of sltSvcSeqNum reaches a maximum value, the sequence number mayreturn to 0.

slsProtocol: a protocol used to deliver service layer signalinginformation of this service, and may be a ROUTE/DASH or an MMTP.

slsMajorProtcolVersion: the major version number of a signaling protocolindicated in SLS protocol (slsProtocol) information—Major version numberfor the signaling protocol specified in slsProtocol.

slsMinorProtocolVersion: the minor version number of a signalingprotocol indicated in SLS protocol (slsProtocol) information

svcInetUrl: indicate a base URL that may connect an ESG or service levelsignaling file for this service to a broadband

URLtype: an available file type of service Inet URL (svcInetUrl)information and may indicate the URL of a signaling server or the URL ofan ESG data server.

FIG. 25 shows component description information according to anembodiment of the present invention.

The component description information describes a watermarked mediacomponent associated with a service.

ComponentAnchor: component anchor information provides information aboutthe first VP1 payload within a watermarked media component.

mediaType: media type information indicates the media type of thiscomponent. “audio” indicates that this component description informationis applied to an audio component, “video” indicates that this componentdescription information is applied to a video component, and “both”indicates that this component description information is applied to bothan audio component and a video component depending on the value of astring.

Descriptor: description information includes information associated witha component consumed by an app.

Priority: indicate relative priority of a component that carries aserver code and an interval code. A recovery file indicated by acomponent having a higher priority value may take precedence over arecovery file indicated by a component having a lower priority value. Ifthis component does not have a priority value, it may be set to 0.

Furthermore, dynamic event retrieval via a broadband may be performedusing an audio watermark.

The availability of dynamic event data may be indicated by a change of aquery flag (query_flag) field value between contiguous VP1 payloadswithin a watermark segment. A receiver may transmit a dynamic eventrequest to a recovery server by issuing an HTTP GET or HTTP GET request.The HTTP GET or HTTP GET request may be issued with respect to aresource specified by a URL constructed from a VP1 payload in which thevalue of a query flag is different from the query flag value of apreceding payload. For example, a URL template may be configured like“http[s]://{hostName}/a336/dyn/{subdName}/{serverCode}-{intervalCode}.dyn.”

The DNS resolution of {hostName} to the unspecified IP address(0.0.0.0132 in the case of an IPv4 address or :/128 in the case of anlPv6 address) shall indicate that a recovery protocol is not supportedfor a code domain. Recovery file requests should not be issued to theunspecified address.

A response to a recovery data request may include a dynamic event. Ifthe dynamic event indicates that at least one signaling update isavailable, a response to the recovery data request may include at leastone signaling file along with a dynamic event. The at least onesignaling file may be delivered as a multi-part MIME messageencapsulated as an MBMS metadata envelope.

A method of obtaining signaling information using a video watermark isdescribed below.

A receiver may obtain a video watermark having a channel ID payload anda signaling URL payload. The receiver may obtain the signaling files ofa multi-part MIME message form using a signaling URL to a signaling URLpayload. The form of the multi-part MIME message may be used in thesignaling URL of an audio watermark recovery file.

A receiver may access or present supplementary content using signalingfiles. The receiver may synchronize audio/video from a cable andsupplementary content using timing information of a channel ID payload.

Each signaling file includes a valid from attribute, a valid untilattribute, and a next URL (“next URL”) attribute. The valid fromattribute and the valid until attribute define the valid interval of asignaling file. The next URL attribute defines the URL of a nextscheduled version of a signaling file. Accordingly, a receiver mayperform the scheduled update of a required signaling file

Dynamic events may appear as the dynamic event payload of a videowatermark. The dynamic event may be used to control an application beingexecuted in a runtime environment. Alternatively, the dynamic event maybe used to signal the availability of an unscheduled update of asignaling file. If the dynamic event is used for app control, a receivermay provide an available event in a specific app. If the dynamic eventis used for signaling file update, the dynamic event includes the URL ofan updated signaling file(s). The receiver may obtain an updatedsignaling file(s) from the URL. The signaling file(s) may have the sameformat as files obtained from a signaling URL, and may include a validfrom attribute, a valid until attribute, and a next URL (“next URL”)attribute.

If a video watermark disappears with respect to a specific timeinterval, a receiver may terminate the presentation of specificsupplementary content. In this case, a receiver may recognize thedisappearance of the watermark as “turn away” to a new service that doesnot support the specific supplementary content. For example, thespecific time interval may be 1.5 second.

If a channel ID watermark appears with respect to a specific timeinterval (1.5 second), if a channel ID watermark appears along with anew combination of a BSID and a channel number, or if discontinuity ispresent in the media time, a receiver may terminate the presentation ofspecific supplementary content and restart signaling acquisition.

FIG. 26 shows a broadcast signal transmitter and a broadcast signalreceiver according to an embodiment of the present invention.

The broadcast signal transmitter 26100 may include a video dataprocessor 26110, an audio data processor 26120, a delivery layer encoder26130, an IP packetizer 26140, and a physical layer processor 26150.

The video data processor 26110 may process video data based on the videoformat of a broadcast system or broadcast service. The video dataprocessor 26110 may embed a watermark payload in the video data. Thevideo data processor 26110 may add the watermark payload to a videosegment.

The audio data processor 26120 may process audio data based on the audioformat of a broadcast system or broadcast service. The audio dataprocessor 26120 may embed a watermark payload in the audio data. Theaudio data processor 26120 may add the watermark payload to an audiosegment.

The delivery layer encoder 26130 may encode a broadcast servicecomponent and SLS information about the broadcast service componentbased on a delivery protocol. The IP packetizer may perform an IPpackage on the broadcast service component, the SLS information, and SLTinformation. The operations of the delivery layer encoder 26130 and theIP packetizer 26140 have been described above with reference to FIGS. 1to 5.

The physical layer processor 26140 may physical-layer-process broadcastdata including a broadcast service component, SLS information and SLTinformation. The physical layer processor and an operation thereof havebeen described above with reference to FIGS. 8 to 10.

The broadcast signal receiver 26200 includes a video data decoder 26210,an audio data decoder 26220, a delivery layer decoder 26230, an IPpacket parser 26240, and a physical layer processor 26250. The broadcastsignal receiver 26200 may perform an operation corresponding to theinverse process of the broadcast signal transmitter 26100.

The physical layer processor 26250 may output a data stream byphysical-layer-processing a received broadcast signal. The data streammay include IP packets. The physical layer processor 26250 may performthe inverse operation of the transmission operation described withreference to FIGS. 8 to 10,

The IP packet parser 26250 may parse an IP packet. The IP packet parser26250 may parse the data of a specific IP necessary to provide aservice.

The delivery layer decoder 26230 may decode at least one of a broadcastservice component and SLS information based on a delivery protocol.

The IP packet parser 26250 and the delivery layer decoder 26230 mayperform the inverse operations of the transmission operations describedwith reference to FIGS. 1 to 5.

The audio data decoder 26220 may decode audio data. The audio datadecoder 26220 may extract a watermark payload included in the audio databy decoding the audio data.

The video data decoder 26210 may decode video data. The video datadecoder 26210 may extract a watermark payload included in the video databy decoding the video data.

FIG. 27 shows a broadcast signal transmission method according to anembodiment of the present invention.

The broadcast signal transmitter may process video data and/or audiodata (S27010). The broadcast signal transmitter may process at least oneof the video data and the audio data and add a watermark payload to theprocessed data.

The broadcast signal transmitter may encode a broadcast servicecomponent and SLS information based on a delivery protocol (S27020). Thebroadcast service component may include at least one of the video dataand the audio data. The SLS information may provide the discovery andacquisition of the broadcast service component. The delivery protocolmay include at least one of the ROUTE protocol and the MMT protocol.

The broadcast signal transmitter may IP-packetize broadcast data(S27030). The broadcast data may include the broadcast servicecomponent, the SLS information, and SLT information. The SLT informationmay include bootstrap information for obtaining the SLS information.

The encoding and IP packetizing based on the delivery protocol of thebroadcast signal transmitter have been described above with reference toFIGS. 1 to 5.

The broadcast signal transmitter may physical-layer-process thebroadcast data (S27040). The physical layer processing and broadcastsignal transmission of the broadcast data have been described above withreference to FIGS. 8 to 10,

The step of processing the audio data may further include the step ofembedding a watermark payload in the audio data. The watermark payloadmay include domain type information, service field information includinga server code, interval field information including an interval code,and query flag information indicative of the availability of a dynamicevent. The server code may identify a server for the acquisition ofsupplementary content, and the interval code may identify the intervalof content in which the watermark payload has been embedded.

The audio watermark payload may signal a display override indicatorindicating that content should be presented without specific overlaidgraphics or another alternate content.

In the audio watermark payload, the availability of the dynamic eventmay be indicated by a change of the value of query flag informationbetween the contiguous watermark payloads within a watermark segment.When the dynamic event is available, the URL constructed from thewatermark payload may indicate the resource of a dynamic event server.

The step of processing the video data may further include the step ofembedding a watermark payload in the video data. The video watermarkpayload may include at least one watermark message.

The video watermark payload may include a display override message. Thedisplay override message may indicate that audio and/or video should beoutput without overlaid graphics or another obstruction. The displayoverride message may include override duration information indicative ofduration for which a display override continues.

The SLS information may include application signaling information thatcontrols an app-based enhancement if a broadcast service includes theapp-based enhancement. Such application signaling information mayinclude at least one piece of information included in the AST of FIG.11.

The present invention provides an additional information signalingmethod using an audio watermark or a video watermark. In a broadcastsystem, to change all of pieces of information, such as SLT, SLS, and anESG, for a temporary or unscheduled event may be inefficient orimpossible. Accordingly, in this situation, necessary information may besignaled using the watermark data of audio data or video data.

In particular, in the present invention, at least one of a videowatermark and an audio watermark may include a display overrideindicator/message. Since the display override indicator is included inthe watermark, a receiver may first provide a corresponding video/audiowhen decoding the video/audio. Accordingly, in particular, if contenthaving very high priority, such as an emergency alert message, istransmitted urgently/immediately, a content delivery probability can beimproved using a watermark. Furthermore, there is an advantage in thatsignaling can be immediately performed because signaling information ofa complicated layer is not used.

Furthermore, at least one of a video watermark and a video watermark mayprovide signaling information for providing a dynamic event. In order toprovide an unscheduled service or a suddenly changing service, a changeof the corresponding service must be signaled. Such signalinginformation may be provided separately from an already transmitted SLTand SLS. In particular, if a change of a service is temporary, to changeboth an SLT and/or SLS may be inefficient. Accordingly, in the presentinvention, dynamic event data may be transmitted using a watermark. Thewatermark may provide a URL indicative of the availability of a dynamicevent and the resource of a dynamic event server. Accordingly, when adynamic event is generated, a receiver may receive signaling informationabout the dynamic event from a corresponding server, and may provide acorresponding service or information about the service.

In the present invention, the broadcast transmitter may control anapp-based enhancement by transmitting the AST. An embodiment ofsignaling information for controlling the app-based enhancement has beenshown in FIG. 11. A service provider can efficiently control thesupplementary function of the broadcast receiver using the AST, such asFIG. 11.

Each of the steps described in the aforementioned embodiment may beperformed by hardware/processors. Each of the modules/blocks/unitsdescribed in the aforementioned embodiment may operate ashardware/processor. Furthermore, the methods proposed by the presentinvention may be executed in the form of code. The code may be writtenin a processor-readable storage medium and thus may be read by aprocessor provided by an apparatus.

Although the drawings have been divided and described for convenience ofdescription, the embodiments described with reference to the drawingsmay be merged to implement a new embodiment. The apparatus and methodaccording to the present invention are not limited and applied to theapparatuses and methods according to the embodiments described above,and some or all of the aforementioned embodiments may be selectivelycombined and configured so that the embodiments are modified in variousmanner.

Meanwhile, the method proposed by the present invention may beimplemented in a processor-readable recording medium included in anetwork apparatus, in the form of processor-readable code. Theprocessor-readable recording medium includes all types of recordingdevices in which data readable by a processor is stored. Theprocessor-readable recording medium may include ROM, RAM, CD-ROM,magnetic tapes, floppy disks, and optical data storage devices, forexample. Furthermore, the processor-readable recording medium may beimplemented in the form of carrier waves, such as transmission throughthe Internet. Furthermore, the processor-readable recording medium maybe distributed to computer systems connected over a network, and theprocessor-readable code may be stored and executed in a distributedmanner.

Furthermore, although some embodiments of the present invention havebeen illustrated and described above, the present invention is notlimited to the aforementioned specific embodiments, and a person havingordinary skill in the art to which this specification pertains maymodify the present invention in various ways without departing from thegist of the claims. Such modified embodiments should not be individuallyinterpreted from the technical spirit or prospect of the presentinvention.

Those skilled in the art will understand that the present invention maybe changed and modified in various ways without departing from thespirit or range of the present invention. Accordingly, the presentinvention is intended to include all the changes and modificationsprovided by the appended claims and equivalents thereof.

In this specification, both the apparatus and method inventions havebeen described, and the descriptions of both the apparatus and methodinventions may be complementarily applied.

MODE FOR INVENTION

Various embodiments have been described in the best form forimplementing the present invention.

INDUSTRIAL APPLICABILITY

The present invention is used in a series of broadcast signaltransmission/reception fields.

It is evident to those skilled in the art will understand that thepresent invention may be changed and modified in various ways withoutdeparting from the spirit or range of the present invention.Accordingly, the present invention is intended to include all thechanges and modifications provided by the appended claims andequivalents thereof.

1-14. (canceled)
 15. A method of delivering a broadcast service in atransmitter, the method comprising: generating an audio component, avideo component, service layer signaling (SLS) information for providinginformation for discovery and acquisition of the audio/video components,and service list table (SLT) for providing access information related tothe SLS information; inserting watermark information into the videocomponent, wherein the watermark information comprises at least onewatermark message block having a watermark message identification (ID),wherein the at least one watermark message block comprises a displayoverride message based on a value of the watermark message ID, whereinthe display override message is used to provide an indication that, fora specified duration, the video component is expected to be renderedwithout any overlaid graphics; and transmitting the watermarkinformation being inserted into the video component, the audiocomponent, the video component, the SLS information and the SLT.
 16. Themethod of claim 15, wherein the display override message comprisesoverride duration information.
 17. The method of claim 16, wherein theoverride duration information included in the display override messagecorresponds to a 4-bit unsigned integer field, further a value of theoverride duration information ranges from 0 to
 15. 18. The method ofclaim 17, wherein when the value of the override duration information is0, an override is immediately over, further when the value of theoverride duration information is different from 0, the override durationinformation represents the number of seconds the override shouldcontinue after the display override message is received.
 19. The methodof claim 18, wherein the watermark information delivers 30 bytes of dataper a video frame or 60 bytes per the video frame.
 20. A method ofprocessing a supplementary content in a digital broadcast receiver, themethod comprising: receiving an audio component and a video componentfor a broadcast service, wherein video watermark payload is inserted inthe video component; decoding the audio component; decoding the videocomponent; extract the video watermark payload from the video component;presenting the supplementary content based on the video watermarkpayload, wherein the video watermark payload comprises at least onewatermark message block having a watermark message identification (ID),wherein the at least one watermark message block comprises a displayoverride message or another message based on a value of the watermarkmessage ID; presenting the video component without any overlaid graphicsfor a specified duration based on override duration information includedin the display override message.
 21. The method of claim 20, wherein theoverride duration information included in the display override messagecorresponds to a 4-bit unsigned integer field, further a value of theoverride duration information ranges from 0 to
 15. 22. The method ofclaim 21, further comprising: continuing an override for the number ofseconds represented by the override duration information after thedisplay override message is received when the value of the overrideduration information is different from 0; and finishing the overrideimmediately when the value of the override duration information is 0.23. The method of claim 22, wherein the audio component and the videocomponent are received via a multichannel video program distributor(MVPD) from a broadcaster.
 24. The method of claim 23, wherein the audiocomponent and the video component correspond to uncompressed contents.25. A transmitter for delivering a broadcast service, the transmittercomprising: a processor configured to generate an audio component, avideo component, service layer signaling (SLS) information for providinginformation for discovery and acquisition of the audio/video components,and service list table (SLT) for providing access information related tothe SLS information, wherein the processor is further configured toinsert watermark information into the video component, wherein thewatermark information comprises at least one watermark message blockhaving a watermark message identification (ID), wherein the at least onewatermark message block comprises a display override message based on avalue of the watermark message ID, wherein the display override messageis used to provide an indication that, for a specified duration, thevideo component is expected to be rendered without any overlaidgraphics; and a transmitting module configured to transmit the watermarkinformation being inserted into the video component, the audiocomponent, the video component, the SLS information and the SLT.
 26. Thetransmitter of claim 25, wherein the display override message comprisesoverride duration information.
 27. The transmitter of claim 26, whereinthe override duration information included in the display overridemessage corresponds to a 4-bit unsigned integer field, further a valueof the override duration information ranges from 0 to
 15. 28. Thetransmitter of claim 27, wherein when the value of the override durationinformation is 0, an override is immediately over, further when thevalue of the override duration information is different from 0, theoverride duration information represents the number of seconds theoverride should continue after the display override message is received.29. The transmitter of claim 28, wherein the watermark informationdelivers 30 bytes of data per a video frame or 60 bytes per the videoframe.
 30. A digital broadcast receiver for processing a supplementarycontent, the digital broadcast receiver comprising: a receiving moduleconfigured to receive an audio component and a video component for abroadcast service, wherein video watermark payload is inserted in thevideo component; an audio decoder configured to decode the audiocomponent; and a video decoder configured to decode the video componentand extract the video watermark payload from the video component,wherein the digital broadcast receiver is configured to present thesupplementary content based on the video watermark payload, wherein thevideo watermark payload comprises at least one watermark message blockhaving a watermark message identification (ID), wherein the at least onewatermark message block comprises a display override message or anothermessage based on a value of the watermark message ID; wherein thedigital broadcast receiver is configured to present the video componentwithout any overlaid graphics for a specified duration based on overrideduration information included in the display override message.
 31. Thedigital broadcast receiver of claim 30, wherein the override durationinformation included in the display override message corresponds to a4-bit unsigned integer field, further a value of the override durationinformation ranges from 0 to
 15. 32. The digital broadcast receiver ofclaim 31, wherein the digital broadcast receiver is further configuredto: continue an override for the number of seconds represented by theoverride duration information after the display override message isreceived when the value of the override duration information isdifferent from 0; and finish the override immediately when the value ofthe override duration information is
 0. 33. The digital broadcastreceiver of claim 32, wherein the audio component and the videocomponent are received via a multichannel video program distributor(MVPD) from a broadcaster.
 34. The digital broadcast receiver of claim33, wherein the audio component and the video component correspond touncompressed contents.